- [Voiceover] NASA's Jet
Propulsion Laboratory presents
the von Karman Lecture,
a series of talks
by scientists and engineers
who are exploring our planet,
our solar system, and
all that lies beyond.
(uplifting, enchanted music)
- Good evening,
ladies and gentleman.
How's everyone tonight?
- [Audience] Good.
- Good, thank you very
much for coming out
between the Thursday night
football, the baseball game,
and the candidate dinner
thing, we're really grateful
you made it out
tonight. (laughs)
So the ability to rove
the surface of Mars
has revolutionized JPL missions.
With more advanced mobility,
new targets like cliff faces,
cave ceilings, and the surfaces
of asteroids and comets
could potentially be explored.
Tonight's talk will
present the work
of JPL's Robotic
Rapid Prototyping Lab,
which is currently
working on grippers
for NASA's Asteroid
Redirect Mission.
This mission plans to
extract a 20 ton boulder
from the surface of an asteroid,
then actually alter it's orbit,
using a method
that could be used
to prevent future asteroid
impacts with Earth.
Our guest will also talk
about other inspired adhesives
and designs currently being
tested on Earth and in space.
Tonight's guest is
the group leader
of the Extreme Environment
Robotics Group at JPL
and the head of the Robotic
Rapid Prototyping Laboratory.
He received two bachelor's
degrees from MIT
in Mechanical Engineering
and Creative Writing,
and an MS and Ph.D.
from Stanford University
in Mechanical Engineering.
At JPL, he currently works on
the Asteroid Redirect
Mission, leading a team
that is developing the robotic
grippers for the spacecraft.
Additionally, he
formulates and leads
several technology
development projects
and also assists
work in JPL's office
of the Chief Scientist
and Chief Technologist.
He and his work have
been featured in
The Economist, Time Magazine,
and as a Popular Science
top 100 innovation of the year,
as well as on the
Discovery Channel, BBC,
and in JPL's own Crazy
Engineering on YouTube.
In 2015, he was awarded one
of JPL's highest honors,
the Lew Allen Award,
which recognizes
individual accomplishments,
pardon me, or leadership
in scientific research or
technological innovation
by JPL employees
during the early years
of their professional careers.
Ladies and gentlemen, please
help me welcome tonight's guest
Dr. Aaron Parness.
(audience applause)
- Thank you.
Hello, everyone, thank
you for coming out.
It's my honor, actually,
to talk to you tonight
about our robotic grippers.
Let's see here.
So we have three basic
technologies you'll learn about.
On the left is a
gecko-inspired adhesive.
Geckos use lots of tiny hairs
on the surfaces of their feet
to stick using van
der Waals forces.
In the center is a physics
that we all learned
when we were about
five or six years old,
walking with wool
socks across the carpet
to shock our siblings or
rubbing the balloon on our head
to get it to stick to the wall.
So we were able to harness that
for sticking to things in space.
And on the right you
see an insect-inspired
adhesive method
using claws or hooks.
This is good for penetrable
surfaces like soft rocks or wood
and for rough surfaces
that are very sturdy
like volcanic rocks.
So the talk is broken
up into four chapters.
We'll start with ARM, the
Asteroid Redirect Mission.
And then we'll move,
actually, backwards in time
to talk about our
rock climbing robots.
These have been in development
for about 10 or 12 years now.
The third chapter is on
the gecko-like adhesives.
And we'll wrap up with a
montage of videos and photos
of some of our
prototypes in the lab.
And I'll try and touch on the
iterative design principles
we use and the rapid prototyping
techniques that enable us
to make these robots very
fast and very cost effective.
Okay, so ARM, the
Asteroid Redirect Mission.
It's a NASA mission, JPL
is leading this mission.
But there's a lot of partners.
Goddard Space Flight Center is
developing the capture module
with significant
contributions from Langley
as well as some teams
back here at JPL.
Glenn Research Center is
developing a high-power
solar electric propulsion
system for this mission,
and Johnson Space Center is
working on a follow-on mission
that would send
astronauts to the boulder
that we're collecting
off the surface.
The spacecraft itself
is going to built by an
industrial partner, and that's
in competition right now.
So there are four
finalists competing
to see who will build the bus.
An animation here shows the
mission during the surface
phase, which is a really
critical phase of the mission.
We're scanning the asteroid.
It's a giant spacecraft.
From tip to tip, those solar
arrays are about 40 meters,
or over 120 feet, much larger
than an NBA basketball court.
We need all that power for
that high-power solar electric
propulsion system, which
is really good for pushing
heavy things like 20 ton
boulders around in space.
As we land, we're gonna absorb
that landing with the legs,
try and cushion ourselves
and use our thrusters
to make sure we don't
bounce, as was what happened
to the Philae lander on
the comet about a year ago.
Asteroids are actually
notoriously hard to land on.
The Japanese also failed in
an attempt about 12 years ago
with a mission called Hayabusa.
We'll use dexterous robotic
arms to place grippers
onto the surface
of this boulder.
And I lead the team that's
developing these grippers.
First, we'll grab onto
the outside of the rock
and then use that grip
to support a drill
that penetrates into the rock
about four or five inches,
which creates a really
strong anchor point
to pull that boulder
off the surface.
Now the boulder has a
mass of about 20 tons,
but on an asteroid, it only
weighs one or two pounds,
and that's because the
gravitational environment
is so low.
So we're actually more worried
about forces like cohesion
between the regolith
and the boulder
than we are about the
weight of that boulder.
Once we have it back
off the surface,
we're gonna wrap it up tight
so we can bring it back
to the Earth-Moon System.
We're gonna do some
other cool things with it
before we depart the asteroid.
So the high-level goals for ARM.
The first one, is
demonstrate the ability
to alter an
asteroid's trajectory.
So nudge it out of the way
if it's coming to hit Earth,
so it's a near miss instead of
a dinosaur killing
kind of event.
The second one is
to get that boulder.
And we're gonna put that
boulder in orbit around the Moon
where it's safe and it doesn't
risk any damage to the Earth
or any of our assets
in Earth orbit,
but where it's
accessible to astronauts
in a follow-on mission and
potentially others, as well.
You may have heard about
some of these companies
that have started up recently
trying to mine asteroids.
We might make that
boulder available to them
as sort of a practice
resource close to home.
The third key goal is to
demonstrate technologies
for NASA's Journey to Mars.
The Journey to Mars is
NASA's plan to send humans
to the surface of Mars in
the late 2030s or 2040s.
To do that, we need a
few key technologies
we don't have today.
One of those is the
SEP, the ability to push
those heavy things
around the solar system.
This would be habitats,
fuel, a rocket
to get us back off the
surface of Mars, food, water.
We wanna stage all of that
at Mars before we ever
send a crew out there,
and we need this
high-power SEP to get it there.
We'll also demonstrate robotics.
Any human mission to Mars
is gonna be a collaboration
between robots and astronauts.
And so, we'll take the
first steps in that here.
And in the follow-on
mission, ARCM,
the Asteroid Redirect
Crewed Mission,
we'll be doing EVAs
at the boulder.
The first time doing
astronaut activities
beyond low Earth orbit
since the days of Apollo.
And we would use
the Orion spacecraft
and the SLS rocket for that.
So the first one of those goals
always gets the
attention, right?
We're gonna push an
asteroid out of the way
so it doesn't hit the Earth.
So I got some of my jokes
from the popular media,
and here you can see,
we've already had
our get out of jail free card.
The dinosaurs saved the mammals
when the first extinction
event came along.
The other one I like,
here are two dinosaurs
sitting together, and in case
you can't read the bottom,
one of them is saying,
"I'm saying now is the time
to develop technology
to deflect an asteroid."
(audience laughing)
So, I couldn't agree more.
Now, some of you may have said,
I've seen this movie before.
What's scary is the interns
that we get into our lab,
some of them haven't
seen this movie,
and they don't remember it.
(audience laughing)
But we send Bruce Willis, right?
If an asteroid is
coming to hit the Earth,
put a nuclear bomb
on the surface
and obliterate
it, right?
And that's one possible method.
And if it was
coming really fast,
and we didn't have
a lot of time,
that might be the
method that we chose.
But there's actually
several other ways
that we might deflect
that asteroid.
And some of them don't require
launching a nuclear bomb
off the coast of Florida.
The method we've selected is
a gravity tractor technique.
We're not sure if it's
the best technique.
We don't know, we haven't
done this before, right?
But it's the technique we think
we can achieve
with this mission,
and so we collect that
boulder, and the combined mass
of the spacecraft and
the boulder is enough
that when we hover
in a halo orbit
on one side of the asteroid,
the gravitational attraction
between us and that
parent asteroid
will slowly tug it, over the
course of several months,
and change its orbit.
So we're tracking all of the
potentially hazardous asteroids
that are gonna come
and hit the Earth.
By the way, nothing
to worry about
for the next 50 to 100 years,
but we're tracking them.
And so we could send one of
these missions out in advance,
demonstrate that we've
pushed it off course,
and then continue to track
it to confirm that it is,
in fact, no longer a threat.
So to get that boulder,
to increase our mass,
to make that gravity
tractor extra effective,
we're gonna use these grippers.
So two of these grippers
that are about yea big
are gonna grab that big
boulder you see in the back.
And that's a mock up that's
at the Satellite Servicing Lab
out at Goddard
Space Flight Center.
So how do you grab a rock?
We use a technology
called microspines.
They're basically sharp hooks
and flexible
suspension structures.
So you drag them
along the surface,
and they opportunistically
catch hold
of bumps, pits,
ledges, ramps, holes.
They only need really
small roughness.
Much smaller than what you
might grip with your hand.
In fact, in these prototypes,
we're using fishhooks.
So you can imagine
dragging a sharp fishhook
across a rock, it's gonna
catch pretty readily.
A key feature of
these microspines,
is that when they catch, they
don't prevent their neighbors
from also trying to search
out a good place to catch.
So they load share.
Each microspine only holds
one or two pounds of force,
but you can use them
by the thousands,
and only need 10% or so to
support a really large load.
So here's what one
of those looks like
as it drags across the surface.
You can see the hook
catches, and when it catches,
you'll notice the yellow sort
of rubber band-like feature
in the back stretches out.
That's when it's supporting
that one or two pounds of force.
And again, we only need
10% or so of these to catch
in order to support the loads
we need for the mission.
So in order to grab a rock, we
need more than just that tip.
Rocks are rough on a macro
scale as well as a micro scale,
and so we use a
hierarchical compliance
to try and conform to
the rock's geometry
at all of the different
length scales.
And since we're doing
this in microgravity,
we use oppositional microspines.
So they're reacting
against one another,
they're all squeezing
towards the center,
so that you don't need any
gravity to load them up.
And they can support forces
that you might exert in
any different direction.
And, of course, since
we're going to an asteroid,
we better make sure
that they can withstand
the extreme environment
that we're gonna find there.
So this is vacuum,
potentially very cold
temperatures, as well.
So those rubber band-like
features I showed you before,
those are not gonna work.
So we've done a
lot of development
to make metallic
versions of microspines
that can withstand
those cold temperatures.
On the first point, the
hierarchical compliance,
most natural surfaces
have fractal roughness,
meaning they're rough at every
length scale you look at.
So as you continue to
increase your magnification
with the microscope, all you see
is the same level of roughness.
So to match that, we use
a hierarchical system
that can conform at all of
those different length scales.
So the microspines grip
at the milometer scale,
we put those into cassettes
that can conform to the rock
at centimeter scale, and we use
the robotic arms to place us
in position at the
10 centimeter,
100 centimeter scale.
So you can see that in action.
Here, you've seen some of
these microspines have caught,
they've stretched out,
they're sharing the load
between any of them that
have stretched out here.
Let's see, you can
see these have caught.
And then these here
have not caught.
So this is more than 10%,
we have a very good grip.
You can see here, some of that
centimeter scale compliance.
Some of these cassettes have
gone to different angles
to conform to the
rock, and some of them
have squeezed in
closer to the gripper.
Another demonstration, you
can see both of those levels
happening here and
supporting some force.
So this is about 25 pounds,
30 pounds on the left and
20 pounds on the right with
some of our early prototypes.
Here's a video that's
showing you how that works.
We have two actuations,
two mechanisms that
are at play here.
One that puts those
cassettes up and down,
and the other one that squeezes
them in towards the center.
So the idea is, you
come into the rock,
you deploy your microspines,
they all conform
to whatever roughness they
find, you squeeze together,
and now you've got a good grip.
You just reverse that
process to let go.
So it's a reusable gripper.
Here's some of the
work we've been doing
to make these
microspines space-grade.
You can see some of
the early prototypes
in the upper left when
we are using those
rubber band-like
polyurethane flexures.
We used some extension
springs, they kind of thing
you would find in a ballpoint
pen, and then we used
these sort of curly Q flexures
where we started using
the aluminum itself as
the spring material.
If you look in the
center, you can see
we went to sort of
zig-zag like flexures.
And on the right, we've actually
been gluing in very thin
steel ribbons that are acting
like a leaf spring to provide
that compliance, mimicking
what the rubber band does.
In the lower left,
we've been experimenting
with different kinds of hooks.
So we have a fish hook,
which is a conical point,
we've also been looking at
razor blades, so more of
a shovel tip, and some more
exotic things even than that.
These are now being
carried on a linkage.
And here you can see some
of this iterative design
I mentioned at the beginning.
We've gone through about four
different linkage topologies
with multiple designs at
each one of those iterations.
And we're trying to make
sure that the microspines
all make contact with the
rock, and that as we drag them
along the surface, the angle
doesn't change too much.
And that's true whether we're on
a flat rock or a round rock.
So we've been
playing around with
the four-bar linkage perimeters
to try and optimize that.
But you can't just
build the prototype,
you have to test the prototype.
And so here is a test stand
for a single cassette.
We're able to execute a motion
where we bring those
microspines into the rock,
drag them along the surface,
and there's a six axis force
torque censor behind the rock.
So we're measuring
all of the forces
during that whole procedure.
I think there's a
video of this, yup.
So here you go, this
is a very soft rock.
We're going to a
carbonaceous chondrite,
which is a type of asteroid
that is usually considered
to be softer than the stony
asteroids, the S-types,
or the metallic
asteroids, the M-types.
But we chose a C-type asteroid
because it has the
most water content.
It has the most
carbon rich molecules.
So it's scientifically
very interesting.
In fact, some folks believe
that asteroid and comet impacts
actually seeded the
primordial soup,
put the building blocks
of life onto the planet
during the late
bombardment period
that helped spark
life on our planet.
So we wanna investigate,
what are those carbon bearing
molecules that are
on the surface
of these C-type
asteroids?
Now what you probably
can't see very well
in the lower right corner
there is a plot of the forces.
So during the drag force,
that blue line goes up
because we're having a lot
of force along the surface.
And then when we start
to raise the center,
which is out of frame, you
see the red line go up,
which is the adhesive
force we're getting
pulling away from that rock.
So we can use this
test stand to optimize
both the microspine design
and that linkage design.
And it sure beats making
a thousand microspines
every time you
have a new design.
But in order to estimate what
that grip strength would be,
we do a statistically
method called
a Monte Carlo simulation
to try and predict
what a grip strength would be at
out of a distribution
of 20 or so tests.
Of course, every once
in a while,
we do make a
full gripper.
So this was a 2.0 gripper.
It was worked on in
collaboration with Thomas Evans
at West Virginia
University, who provided
the robot arm to do testing.
So this gripper has
about 650 microspines.
It's got them in
two different rings,
and it turns out that
was a bad design.
So in the 3.0 gripper, we
went back to just one ring.
The reason it was bad is
because the inner ring
and the outer ring would
be at different angles
if you were on a flat
rock versus a curved rock.
And so the angles of those
hooks essentially meant one ring
was very effective and the
other ring was not effective.
So we just decided,
let's just pick one ring.
You can see the same
kind of data coming in
in the upper left as we're
starting to support loads.
In this test, we get up to,
that's about 100, 120 newtons.
Before you see us slip,
and then it reattaches
and starts to grip again.
A question we get all the time
is what happens if there's
dust on the surface?
And since the hooks
are very sharp,
as long as that
dust isn't too deep,
they'll just dig
right through it.
And so here you can see a
prototype that was built,
where we're able
to pull out a rock
that is completely
covered in dust.
And so on the asteroid
surface, it may be
a dusty environment, but we
don't expect that dust layer
to be so deep that we won't
just cut right through it.
So some of the
prototype evolution.
We started with rapid
prototype 3D printed parts,
moving as fast as we could,
designing in plastic.
And then we move into
the aluminum grippers,
which are larger,
that's the actual size
we're gonna fly on the mission.
So we call this the 2.0 Tool.
We actually built two of
those grippers at that size.
So here's 2.1, has some
slightly different electronics
and different microspines,
the hoop flexures down there
where we were testing
out some new concepts.
Currently, we're actually
building the 3.0 Tool.
So this is coming
together right now.
You're seeing pictures
hot off the presses.
This is maybe a day or
two ago we took this one.
This is our drivetrain.
It's basically like the gearbox
or the transmission in your car.
It's got a two-stage clutch,
and it powers six different
mechanisms in the Tool.
The 3.0 Tool is actually
much more complex
than the 2.0, 2.1, any
of the previous Tools
because we've added a
rotary percussive drill
down the center.
Here's a underside view
of this drivetrain.
And here's that drill.
So it's a little
hard to make out
everything that's going on,
but you've got things like
you're chuck, which
is how you connect
your drill bit to the drill,
a spindle, percussions,
this is a hammer drill,
an anchor deployment,
I'll talk about that in a little
bit, and a feed mechanism.
And we're lucky, because
at JPL there's been a lot
of development work already on
how to drill in outer space.
So Curiosity, of
course, has a drill,
a rotary percussive drill,
and the Mars 2020 mission,
which is a bit ahead of us
in the development timeline,
has also got a drill.
So we've tried to leverage all
of the lessons that they've
learned and all of the
design experience they have,
incorporating those
things into our drill.
Here's the Tool in
its current state
as its getting assembled.
So it's only the drill and
the drivetrain right now.
The gripper is still
getting put together.
But that drivetrain is really
complicated because we've made
a choice not to fly motors
inside our Tool, but instead
to use the motors that
are in the robotic arm
to drive our Tool mechanically.
So there's a tool drive output
at the end of the robotic
arm, and we're using
those outputs to
power our mechanisms.
Trouble is, there's three
outputs on the robotic arm,
two rotary and one linear,
and we have six mechanisms
on our Tool that
we need to operate.
But we don't have to operate
them all at the same time.
So we use a clutch.
Same way you don't
drive your car
with all the gears
running simultaneously.
We index between
whether we're gripping
or drilling or anchoring.
So this ended up
being pretty complex,
but what I think is some
pretty beautiful hardware.
I'm a mechanical
engineer, though.
(audience laughing)
So I like all these
kinds of pictures.
Now with that drill,
our operations
get a little bit more
complex, as well.
So we allow the robotic arm
to bring us into contact
with the surface and align
us, make sure our drill bit's
facing orthogonally to
the rock wherever we are.
And we deploy the gripper,
we bring those cassettes
down onto the rock and
then squeeze them in
to establish a grip with
all of the microspines.
Once we've got that grip,
we're able to drill.
The gripper is
basically there to react
the forces and torques of
drilling in microgravity.
An analogy I like to use is
if you're on an asteroid,
and you've got your drill
that you use at home,
if you push that drill bit into
the surface, on an asteroid,
you're going to be pushing
yourself into outer space.
And if you pull the trigger on
that drill to start drilling
it gets worse, 'cause you're
gonna start spinning around
(audience laughing)
the drill bit
instead of the drill bit
spinning in the borehole.
So we use a microspine
gripper to react those loads
and make sure that the
drill goes into the rock
and make sure it
spins and the robot
and the spacecraft don't spin.
So once we've drilled
to a certain depth,
we do an anchoring process.
We actually cut a groove in
the bottom of the borehole
that locks us in
geometrically to the rock.
So we do that by flanging
out some little cutters,
and I'll show you a picture
of that in a second.
But that creates a very strong
anchor that we're now able
to pull on with thousands
of newtons of force
to extract the boulder
off the surface.
So of course we have
to prototype this.
So we've put a drill down the
center of our 1.0 grippers,
and because we are prototyping,
we used the best, quickest,
dirtiest drill we could find,
which was at Home Depot,
it was a Bosch Rotary
Percussive Drill.
We chopped it up, put the
innards into our own motor,
and then had a prototype working
where we were practicing
drilling into rock
I think within about one summer.
You can see on the right,
it's actually anchored itself
to the ceiling, and is not only
supporting the weight
of that whole assembly,
but is also drilling
into the ceiling.
So it's supporting
the loads it takes
to drill into the ceiling.
Now that's a harder than zero
G test going into the ceiling.
Microgravity is
actually true zero G.
So what we did was
fly on the Vomit Comet
and test this mechanism.
Now show of hands, who's
heard of the Vomit Comet?
All right, that's
about three quarters,
that's a good audience,
you guys are well-educated.
For those that don't
know, it's an airplane
that NASA operates that
flies a parabolic trajectory.
So basically, the airplane
throws you up into the air
and then tracks you
as you're in freefall,
as you're experiencing zero
G as you would in space,
and then you go into a nosedive,
and at the last second,
they pull out of that
parabolic trajectory,
they basically catch
you, and you experience
double gravity for
the rest of that,
the bottom part of the parabola,
and then they go right
into the next one
and just throw you
in the air again.
So you get about 20 or
25 seconds of zero G,
where you're floating
around, it's very zen.
People ask if it's like a
roller coaster, it's not.
It's very calm.
But then when they catch you,
and you go into double gravity
and you're glued down
against the floor,
that feels a little bit
more like a roller coaster.
And they give you very strong
motion sickness medication
so that you don't
have the effect
after which the plane is named.
(audience laughing)
So what you see here
is our prototype.
It's on a Stewart Platform.
And that Stewart Platform is on
air bearings that have brakes.
So basically the whole drill
and the rock float during
the zero G portion, but when
we go into the two G portion,
those brakes seize up and
lock everything in place.
So it's a way for us to
not have our hardware
crash into the floor every
one of those parabolas.
And by the way, on a single
flight, they do 40 of those
back to back, takes about
an hour, and it's exciting.
We've done, I've done
now, 12 of these flights.
So I have just over an
hour of zero G time.
So if I keep up this pace,
I'll never catch up
to the astronauts.
(audience laughing)
It's always fun.
Now this is my favorite
video for another reason.
You see all the
debris coming out.
This is my favorite video
I'm going to show all night.
But sort of for nerdy reasons.
You see all that debris coming
out, and that's a barometer
to tell what part of the
spacecraft a person works on.
So if you show this to
robotics people, they're like,
ah, this is awesome,
that's so cool.
And you know that
they're used to
interacting with the surface.
If you show it to someone,
and they have very pale face
and start to shake, you
know that they work on
camera systems or remote
sensing or they have delicate
equipment that's back at the
backside of the spacecraft.
So on the actual asteroid
mission, we'll have a shroud.
We'll make sure we
catch all of this debris
so that it doesn't contaminate
all of the other activities
we're going to be doing.
Now the final reason I
think this is so cool,
is you can see that
dust cloud kind of shift
a couple of times
during the video, right?
And this is, I didn't know this
until I saw this video
and asked the question,
I thought a computer was
flying this, the airplane.
Turns out it's actually the
blue suiters, the pilots,
who are manually steering,
trying to keep you
in that sweet spot of zero G.
And so every time you see that
dust cloud change directions,
they're making a
small adjustment,
trying to keep the plane
in that perfect freefall.
So it might be .01
G, minus .02 G,
and they're actually very
talented at keeping you
in that perfect zone
throughout the 20, 25 seconds
that you have to
do your experiment.
So a little bit more about
the anchoring drill bit.
That's a prototype on the right
that we test in
pre-drilled boreholes.
So we drill with a commercial
drill, we put this prototype
in, and then practice the
anchoring procedure only.
And you can see in the
colorful diagrams there
how those anchoring
teeth flare out.
And so this happens at
the bottom of the borehole
as you're still
spinning the drill,
but you're not pushing
the drill in any further.
And so what you're left
with is a little groove.
I hope you can see this one.
A groove in the rock
that you can pull on
with a lot of force.
So here you can see again where
we've cut one of these open.
You can see where
that groove was cut
and where those teeth
were actually pulling.
So we've been able to pull
on some of these rocks
up to a few thousand pounds.
And we've tested on all
different kinds of rocks.
Because we've never been to
the surface of an asteroid,
we don't actually have a
very good understanding
of the strength of the boulders
that we're gonna find there.
So we have meteorite data
and we have bolide data,
which is measurements when
asteroids hit the atmosphere
at what point they break up.
And from those two sources
we can make some guesses
about how strong the
rocks are on an asteroid
and specifically on
a C-type asteroid.
But the range is pretty big,
like two orders of magnitude.
So we have to design
a very robust tool.
Now it's gonna seem
like I'm kind of
cutting this portion
of the talk short,
and that's because it's
a work in progress.
So you've literally
seen all the way
up to where we are today.
We're planning towards
a launch in 2021.
So if you keep
following the news,
you're gonna see a lot
more about the ARM Mission,
Asteroid Redirect
Mission, and you'll
see all of our good
results from that 3.0 Tool.
But now we'll move into the
second phase of the talk.
Second chapter,
we'll look at some
rock climbing robots
that we've built.
So on the right, that's
Christine Fuller and I
out at the Mojave Desert
climbing in some lava tubes,
place called Pisgah Crater.
Here's our rock climbing
robot, and people ask,
why would you want a
rock climbing robot,
except that it's super awesome.
(audience laughing)
It turns out that there
are a lot of places
on Mars and other planets
that we can't access with the
six-wheeled rocker-bogie
rovers that we have now.
So we see stratified
layers in the rock
on outcrops on Mars, but
we can't get to them.
We've tried, actually,
but because the rovers
can only drive on a 20,
maybe 30 degree slope,
we can't actually
access those outcrops.
And if anyone's been
to the Grand Canyon,
you see those different
layers, and they tell you,
oh, you can look back in time
by looking at the
different layers, right?
The oldest ones
being at the bottom.
So that's true on Mars, as
well, and wouldn't it be great
to deploy instruments at all
of those different epochs
in Mars's geologic
evolution and learn about
the history of the planet?
And it would be great,
and we hope to do that,
but we can't do it with the
rovers that we have today.
So the start of
rock climbing robot
actually predates
me joining JPL.
I was in graduate
school at Stanford,
and we were working on
vertical climbing robots
actually for the military
to try and climb up
the outsides of brick buildings.
So this robot was made
by Boston Dynamics.
Many folks know them
for making robots
like BigDog and Atlas, WildCat.
They're a very good
company for making robots.
This is a lesser known
robot called RiSe,
and I worked on building
the feet for this robot
with my lab at
Stanford University.
The professor there
is Mark Cutkosky.
It used the first
versions of microspines,
which used gravity just
to engage themselves.
So this robot would only
climb in a straight line,
straight vertically.
Couple of years later, I
took a little bit of break
from my Ph.D. for five or
six weeks and worked for
the Discovery Channel on a
show called Prototype This!
And I'm guessing many
of you didn't see it
'cause it got cancelled
after the first season.
But here, we're showing
paddles, where Lynn,
who's a professional rock
climber, is scaling the outside
of a parking garage
in downtown Oakland.
Each one of those panels
has 1500 microspines,
which is why it took me
six weeks to make them.
And I was very excited,
this was the first time
we had taken them
out and tried them.
So a huge relief.
A younger, skinnier,
very happy version
of me there in the red shirt.
(audience laughing)
So I mentioned these
innovations before.
When I came to JPL, the
question was, how can we use
these climbing
robot technologies
for NASA
applications?
So on Mars, it's not a brick
wall, it's a cliff face, right?
So the same three
things I mentioned.
Conform to the roughness,
opposing microspines
so you can resist
forces in any direction,
and make them out of
space-grade materials.
And so that's what we did.
You can see us testing, pulling
these in different angles
because we've got
that opposed gripper.
Again, notice this
doesn't look like
the ones I've shown you before.
We go through iteration
after iteration.
We make tons of prototypes.
We have a big wall full
of dead prototypes.
That's fun to look at if
you ever get to take a tour.
Here you can see testing,
again, at different angles.
And we test it on all
different kinds of rocks.
And you'll notice the
bottom line there says
limited performance
on granular materials.
These are things like
pebbles, sand, regolith,
powder, that sort of thing.
And I'll tell you a secret,
in an academic paper
or in a talk like this,
if you see something
that says limited
performance, that means zero.
(audience laughing)
This is really a technology
for consolidated rock, right?
If you want to
grip the sand dune
or the regolith field on
the asteroid or the comet,
you need a different
kind of gripper.
You might use the
same kind of robot.
You might use the same autonomy
and the same perception
system, but you're gonna want
a beach umbrella
kind of gripper.
Something that's meant for sand
or these unconsolidated
materials.
So a cool spin-off we got to do.
Because we're able to make
these grippers pretty quickly,
is we made a hand actuated
version of the gripper
that would function
in saltwater.
So this is a neutral buoyancy
test bed that the astronauts
use to practice mocking
up their missions.
Buzz Aldrin, way back
in the Apollo day,
realized that if you wanted
to practice zero gravity
for a long time, one way
is on the Vomit Comet,
but another way
is in a scuba suit
where you can make
yourself neutrally buoyant,
which is actually a
pretty good simulation
for what it's like to
be in zero gravity.
And so here, they're
using microspine grippers
to anchor themselves
to the floor,
which is a simulated
surface of Phobos.
Phobos is one of
the moons of Mars.
And then they're doing other
operations, other samples.
The moons at Mars
are way, way smaller
than the moons of Earth.
So they are actually
microgravity environments
like an asteroid or a comet.
I think there's
actually some debate
about whether those moons
are captured asteroids
or if they're
actually, truly moons.
Here's the rock climbing robot.
This was a video we put
together a couple years ago.
So just like you see different
iterations of the grippers,
we have different
versions of the robot.
So this is LEMUR 2B.
So there's a LEMUR 1, 2,
2A, 2B, we actually have
a LEMUR 3 now, which I'll
show you in just a moment.
I'm gonna skip ahead a
little bit if I can here.
Let's see.
That's the more exciting part.
So this is sped up, as well.
Because when we did
this project,
LEMUR 2B already
existed.
So we said, hey, can
we just use
this robot with our grippers?
Again, try and prototype
and demonstrate something
as fast as we can.
And Brett Kennedy, who had
designed and built this robot,
said sure, but I designed
it to have a peg for a leg,
which only weighs 100 grams.
And I came along and put a one
kilogram gripper on the end,
so it's at the maximum amount
of torque that the motors
can put out in order to
do these kinds of motions.
So all of the videos
are sped up quite a bit.
But as you might know,
going fast, for JPL,
is not necessarily a priority.
It's safety and reliability
that are more important.
So Curiosity on
the surface of Mars
at most goes about
100 meters in a day.
So if you had a
rock climbing robot
that might be able to go two
or three meters in a day,
over the course of a year or
two years, you're actually
gonna cover that cliff
face from top to bottom.
So here's LEMUR 3.
You can see it's got
a lot more joints.
With more joints, it's able
to do more complex motions.
So LEMUR 2 only had three
degrees of freedom per limb,
which meant three motors that
could turn in any given axis.
LEMUR 3 has seven degrees
of freedom per limb,
which is similar to what
you have in a human arm.
So it can put its foot any place
in space at any orientation
plus have one extra degree
of freedom to enable it
to move its body around or
do other sorts of things.
Now this is not a
test wall in our lab.
One of my favorite
parts of the job
is that we get to go
camping with the robots.
And we go out and
we do field tests.
So this is at a pretty
spectacular cave
called El Malpais in New Mexico.
El Malpais is the
national monument,
the cave itself is
called Big Skylight Cave.
You can guess why.
So we climb down in here
and we have the robot
practicing on the side
of this lava tube.
Lave tubes are
really interesting
because we see them on Mars.
So you can see our field
site that we practice on
in New Mexico on the right,
and you can see a picture
that was taken from an
orbiter at Mars on the left.
And the similarities
are really remarkable.
What you'll notice is the
difference is that our
lava tubes on
Earth are smaller,
so 20 meters
versus 50 meters.
Turns out the size of the lava
tubes seems to correlate to
the amount of gravity that
exists on that planet or body.
So on Earth, we see
20, 30 meter max.
On Mars, we see 50,
some even at 100 meters.
On the Moon, we can see them
up to 200 meters in diameter.
So you can imagine
that is a giant cave.
Now caves are really interesting
because they're
preservation environments.
So if you get into a cave,
the environment is
relatively stable.
It never gets too hot,
never gets too cold.
On Mars and the Moon,
you're protected
from radiation as well.
So samples that may be
susceptible to that radiation
haven't volatilized and escaped.
You may have things
that are preserved.
It's no accident that
we find cave paintings
from early man in caves.
It wasn't that they didn't
like painting out in the light,
it was that all of the
paintings on the cliff walls
got washed away and
weathered away over time.
So the only ones we find
now are in the caves.
Here's another picture
of caves on Mars.
We actually have thousands
of these skylights
that we've observed.
And you can see here, several
of them along a sinuous rille.
It sure looks to me
like that's a cave
that's probably
connected underground.
And you can see
from the scale bar,
it's several miles in length.
The other thing that's
good about having
a preservation environment
is if you're a person,
you're not getting
cancer, being blasted
by that radiation
on the surface.
So it may be that we
evolved from cave people
and we will return
to being cave people
when we visit Mars and the Moon
to protect ourselves from
that radiation when we sleep.
Now caves are amazing,
but you might also
want to visit those cliff
faces, as I mentioned before.
And there's plenty
of them on Mars.
The Grand Canyon equivalent
on Mars, Valles Marineris,
is actually much, much
larger than our Grand Canyon.
So you can imagine a
pretty epic mission
having a robot climb from top
to bottom or bottom to top.
And just to emphasize the point,
I don't know how many people
have seen these photos,
they were published by Curiosity
and the Mars science laboratory
team just a few weeks ago,
but these are Murray
Buttes in Gale Crater,
and they really show some
spectacular cliff faces,
and I would love to have
that be our next test site.
And just to emphasize the
cameras that they have now
on these missions
are incredible.
The detail we see, the
layering that you see,
there's so much to explore
beyond what's on the floor.
So rock climbing robots are good
for cliff faces and for caves.
They may also be good
for microgravity.
So moving in
microgravity is more of
a climbing problem
than a walking problem.
If you let go in microgravity,
you fall off, right?
So Itokawa, which
is the asteroid
that the Japanese
visited,
it's about 500 meters across,
the long part of that potato,
and it has the equivalent of
.0003% of Earth's gravity.
And that's pointing sort of
in weird directions, as well,
because that's not a
perfectly spherical body.
So if you jumped off the
surface of Itokawa, no doubt,
you end up in outer
space, never to come back.
If you drop a baseball
on the surface,
takes many minutes for it to
fall down and hit the ground.
So keeping yourself anchored
to the surface is a good idea.
Now these bodies are littered
with boulders and other kinds
of terrain that we might
want to crawl around on.
As I mentioned, the microspines
are good for consolidated rock.
We might have that auger
or that beach umbrella
for the weaker,
granular materials.
The picture on the right was
taken by the Rosetta mission.
That's comet 67P,
I always say CG.
That name is tremendously long.
And these are
incredible pictures,
but wouldn't you like to
have a rover on that body
the same way we have
a rover on Mars?
If you did, you might
start at one lobe
and traverse across the neck
and onto the other lobe.
There's a hypothesis
that 67P might have been
two comets that
got fused together.
We don't have a great way of
testing that because there's
redistribution of the granular
materials on the surface.
So if that fusion happened,
it's kind of been
obscured by now.
But if we could drill, if we
could get under the surface,
we could learn all
kinds of secrets
about the history of that comet.
So you can see places
I've marked with red X's
as example locations in
different geographical units
that we might try and drill.
Here's just a closer in picture,
example pathways
that we might take.
And I'll wrap up with our
beautiful artist concept
of what a rover mission on
the surface of an asteroid
or comet would look like.
I was told, though,
actually if the Earth
is this big in the picture,
it's a bad day for the Earth.
(audience laughing)
We might need that asteroid
deflection technology.
But it makes for a good picture.
Okay, so chapter three
is gecko-like adhesives.
Now gecko adhesives
are very different
than the claw-based approaches
I've been talking about.
You'll sometimes hear me refer
to them as ON-OFF adhesives
because one of the most
remarkable properties
is a gecko can turn the
stickiness of its foot
on and off depending on
which way its pulling on it.
So imagine having duct
tape that you could switch
whether it's sticky
or not sticky.
So geckos, amazing, nature's
best climber by far.
That adhesive is reusable.
We've actually tested
it with some colleagues.
30,000 cycles and the gecko
adhesive didn't wear out.
Can you imagine
if you're a gecko
and your foot stops
sticking after 10 steps,
you're quickly a dead
gecko, which is bad.
(audience laughing)
That ON-OFF behavior,
and the physics
behind this is van
der Waals forces.
And if you remember your
high school physics,
van der Waals forces are
the temporary and weak
interactions that you get
between two electron clouds.
So you bring neutral
atoms very close together,
those electrons are flying
around all over the place,
they don't stay in one spot.
So at any given minute, if
you slice the atom in half,
a few more electrons may be
on one side than on the other.
And if those atoms are
really close together,
they're gonna induce
a matching polarity
in the electron clouds
that are close by.
So you get this net
attractive force
called van der Waals forces.
Way weaker than
electromagnetic forces,
way weaker than if the
atom is missing an electron
and the other one
has an extra electron
and you've got a covalent
bond or something like that.
But the gecko can
use those forces
because of all the tiny
hairs it has on its feet.
Now some great videos
of geckos here.
One toe supporting its
entire body weight.
So it's really sticky, and
that's on glass, by the way.
And if you look on the
video on the right,
you can see some really
rich biology going on
with the curving spine
and the trot gait
and its curling its toes.
Geckos could go from the
floor to the ceiling in here
in about two seconds.
They take ten steps per second.
Now imagine trying
to peel duct tape
and put it back on the surface
ten times in one second.
You can't because you can't turn
the stickiness of duct tape off.
But because the gecko, when
it pulls down on the adhesive,
is sticky, and when it
releases that weight,
is un-sticky, it
can fly up the wall.
So to really
appreciate the gecko,
you have to have a microscope.
So geckos have this hierarchical
structure of tiny hairs.
The only ones you
can see with your eye
are up here in the upper left.
They're called lamellae,
and they're flaps.
They look like flaps, they're on
the sort of milometer scale.
Growing on each of those
flaps is a forest of hairs,
tiny hairs called
setae that are about
five microns in diameter maybe
a hundred microns in length.
For reference, a human hair
is about a hundred
microns in diameter.
So these hairs are
20 times smaller
than the hair on your head.
They grow at an angle, as
well, which is important.
At the ends of those
hairs, though, down here,
you see it kind of tufts
like a head of broccoli.
And that's because
you have branches.
Each one of those hairs tufts
into dozens if not hundreds
of branches that are at
the single micron scale.
Really, really small.
And those branches
terminate in spatulae,
which are only tens
of nanometers thick
and 100, 200 nanometers across.
And they kind of
look like a spatula,
although that's a
coincidence with the name.
Those are what makes
contact with the surface
and what uses those van
der Waals forces to stick.
So the genius of
the gecko system
is that it has this intricate
suspension structure
behind those spatulae that
help it conform to the surface
and load share without pushing
the animal back off the wall.
I can jam my hand into a
surface and generate some
van der Waals forces, but
because the deflection
of the tissue in my hand
is greater in terms of
a spring back force
than the adhesion I get
from the van der Waals forces,
I can't climb up the wall.
Unfortunately, that
would be great.
But a gecko can do it.
Now manufacturing
something that intricate
is still probably 50 years out.
We just don't have
the technology
to make something like
the gecko is able to grow.
We can make thing at the
nanoscale like nanotubes.
We can make things at
the milometer scale.
But making them together, and
non-coplanar and branching,
it's just too much.
So as an engineer, I
don't wanna wait 50 years
for the technology
to come around.
So we do biomimetics.
We're not trying
to copy the gecko,
we're trying to
learn the lessons
and apply them in our robots.
So one of the lessons
is this directionality.
You can see this
hair has an angle.
These hairs are about 20
microns across the base.
So they are about
five times smaller
than the hair on your head.
And they're made out
of a silicone rubber.
So gecko hairs are actually
made out of beta-carotene,
which is like a
fingernail or lizard skin.
It's rough.
We cheat by using a
rubbery-like material.
Not a sticky material, but
something a little softer
that lets us get a
little bit more adhesion.
Just because we can't
match that geometry.
You can see that same property
if you pull the gecko
hairs along the surface,
they bend over, you get a
high, real area of contact,
lots of van der Waals
forces, and they stick.
If you push them in
the opposite direction
or you don't load them at
all, it's only the very tips
of these hairs, it's only
this point, right here,
that makes contact with the
surface, and you don't have
any van der Waals
forces, it doesn't stick.
We add a tip to these features,
we've been collaborating
with Elliot Hawkes
and my old advisor Mark
Cutcosky at Stanford,
we've really never
stopped working together
since I was a young
master's student,
to add this mushroom shaped tip,
and that gives you
about twice the adhesion
'cause you have a thin
film effect at the edges.
So the way we make these,
I'll try and do it very quickly,
I'm gonna speak MEMS
technology here for a minute.
So if you don't
understand, don't worry.
We use a quartz wafer, and
then we hard mask that in metal
so that we can do an
exposure through that wafer.
Quartz is transparent to
UV light so we can have
UV light come through this
wafer from the back side
and expose where we
haven't blocked it off.
We then align and do
a vertical exposure
and then develop, and what
you end up with is a mold.
So we have a negative
version of that shape
that we can cast into
over and over again.
So we use that silicone rubber,
which starts kind of
like 5 Minute Epoxy.
It's two parts of liquid,
you mix it together,
you pour it in, and
voila, it solidifies,
and you can peel it out.
You do that over and over again.
To understand the
behavior, we test that
at all different angles.
So we pull on that gecko
material with sheer
or with no sheer, and
the key point here,
is this goes through the origin.
Which means if you don't
pull across the surface,
it doesn't stick.
And if you release that
force across the surface,
it comes off.
You can see with the more force
along the surface you have,
the more stickiness you have.
This axis is your stickiness,
and this axis is your
pulling along the surface.
And that maxes
out at some point,
and then you kind of asymptote.
So I'll get back to a
more interesting thing,
here's the first robots
that we were testing
with this gecko-like adhesive.
We called it Stickybot.
In fact, this is Stickybot
2, so I was learning
iterative design even
when I was in school.
You can see, it's
very gecko-like
in more ways than just the feet.
Sangbae Kim was the main
guy who designed the robot.
I really worked on the
feet for this robot.
He's now a professor at
MIT, you may have seen
his Cheetah robots if you've
seen any of the YouTube videos.
I like to joke, people
in Thailand come down
and they see a gecko running
up their kitchen cupboard.
In our lab at Stanford,
we would come down
and we would see a robot
gecko running up the cupboard.
This gecko used gravity to
engage that ON-OFF behavior.
So again, it only
climbed in a vertical
straight line against gravity.
We have to do a
trick if we're gonna
get it to work in zero
gravity, in space.
And it's the same trick
a gecko does, actually.
You can see here, if a
gecko's sideways on a wall,
it orients its feet so
that gravity is pointing
in the preferred direction
to make their feet sticky.
And if they flip upside down
to go head first down the wall
they actually rotate their feet,
again so that they're in
the preferred direction
so gravity turns
the stickiness on.
The first person
to observe this,
or at least the first
person to write it down,
was actually Aristotle
in one of his books.
So kind of cool side note
is I got to cite Aristotle
in my Ph.D. thesis,
(audience laughing)
which I thought was great.
Now so we use that
trick to our advantage
in the same way we do
with the microspines.
Put two gecko pads in
opposition, squeeze together,
and you're gonna get
an adhesive anchor
that can support loads
in any direction.
You can do it with two pads,
you can do it with
a lot of pads.
Of course, since it's
supposed to work in zero G,
we gotta take it on the
airplane, test it out.
So here's me grappling
a free-floating cube
during one of those
zero G moments.
So this is a video, again,
collaborating with Stanford
to demonstrate some of the
properties of these grippers.
One of the key things is
you don't have to push
it into the surface.
You just have to pull
along the surface.
So unlike duct tape, again,
where you have to sort of
make sure it's pressed down
firmly to get it to stick well,
with a gecko-like adhesive you
just touch it to the surface,
and it sticks.
And similarly, you can
release it with zero force.
It doesn't fall or push that
plate away when he lets go.
We've done testing here at JPL
in a thermal vacuum chamber
so it does work in the
environment you find in space,
minus 60 Celsius, full vacuum.
We've done over 30,000 cycles
with our synthetic
gecko adhesive.
And here we're demonstrating
one of the use cases,
where we might try and grapple
a piece of orbital debris,
a piece of space garbage, and
try and tow it out of the way,
make sure it doesn't
hit astronauts
like that
movie Gravity,
make sure that we can
protect our assets.
Now we wanted to test a
hundred kilogram cube,
which is basically a
refrigerator, and we asked NASA,
can we fly a refrigerator
inside the airplane?
And they said, heck no.
(audience laughing)
And so we were bummed
for a couple of days
until one of our
students, Jonathon there,
said y'know I'm
about 100 kilograms.
And so we put a vest
on him, and he became
the high inertia target.
And that's one of our
other interns at the time,
who now works here,
grappling him.
Another facility we have at JPL
to test in a zero
G-like environment
is the Robo-Dome or the
Formation Control Testbed.
It's like a giant
air hockey table,
but these robots are pumping
the air out the bottom
instead of the air
coming through the table.
The robots weigh
about 800 pounds each,
but you can push
them with your pinky.
And in this demonstration,
we used thrusters
on the gold robot to
chase down the blue one,
grapple it with
the gecko adhesive,
and tow it back
to a set position.
So this is a mission that
you might see in space
if you're grappling a
satellite that's gone
out of its preferred orbit
and putting it back in place,
maybe doing repair,
refueling on that satellite.
Of course, I'm a roboticist,
and so I wanna see robots
crawling around on everything.
Here's an artist
concept of a robot
inspecting the outside
of the space station.
And if we send humans to
Mars, that journey to Mars,
you may find robots to
maintain that space station,
make sure it's functioning,
do light repairs.
So we've done some
work on this, as well.
In this case, we're using
a counterweight to reduce
the gravity and allow us
to climb around in zero G.
Now I knew you guys were
gonna be a smart audience,
and so I sped up the video
that was already sped up
so any of those numbers
you see, multiply by three.
So you can see it
gripping and releasing.
And you can see this is LEMUR
3 just with different feet.
We use LEMUR 3 for rock
climbing with the microspines.
Use LEMUR 3 for ISS inspection
kinds of challenges
with gecko grippers.
Now earlier this
year my first piece
of hardware got sent to space.
This was in May.
I did not take this picture,
but I was very close to
this spot, and my picture
looks nothing like this.
(audience laughing)
But here's a resupply
mission going to the ISS,
it was a night launch, it
was awesome to see it go.
And we put a few gecko grippers
in the hands of the astronauts.
So here's Jeff Williams.
He's attached a gecko
gripper to the bulkhead.
And then he's gonna
take out a force gauge
and tug on it and
measure the force.
We also had them
leave those grippers
in place for a few weeks,
just to demonstrate that
it doesn't wear out,
doesn't need any power
to stay attached.
And my favorite part right here,
this is the first
time he does it,
he thinks it's gonna pull off.
Then he realizes, oop,
I gotta brace myself,
because that's a sticky gripper.
There are opportunities to use
this technology here on Earth.
We've partnered with
a startup company
called Perception
Robotics that's here in LA
that wants to put gecko
grippers onto the factory floor
to do pick and place operations,
those kinds of things.
And they sent me
this picture one day,
which I was not expecting,
where they were at
a small business event,
and President Obama
and Chancellor Merkel stopped by
and I actually built that
gripper that we had given
to the company to do testing
and demonstrations with.
So they sent me this
picture, and I--
Holy cow.
(audience laughing)
So we're onto the fourth
chapter, and we're gonna do
a rapid fire kind of
whirlwind through some of
the early stage prototypes
we have in the lab.
So we've put some of these
adhesive technologies
onto wheeled robots.
We're trying to
miniaturize robots.
Get them as small as possible.
So you can see here
the microspines
climbing up rough surfaces.
(audience laughing)
And you'll notice
there's no safety line.
We try and make these
sort of crash proof
so that they can survive
if they are to fall off
(audience laughing)
or if we intentionally
drive them off.
This was especially
fulfilling 'cause we eat lunch
right next to these stairs,
so we would look at it
every day and say,
one day we're gonna
have the robot climb
up those stairs.
You see Kalind Carpenter
there controlling the robot.
He did most of the work
here to make that a reality.
So it was another fun
day when we were out
at the tallest brick
building we could find,
it's about six stories.
The robot made it all
the way to the top.
And then we realized that the
latch to the roof was locked.
(audience laughing)
And we couldn't get up there.
So we brought out a fishing
net and tried to catch it.
And we made it fall
off, and we missed.
(audience laughing)
So one story kind of
falls, we can survive.
That six story was
a little tough.
But here you can see some
of our impact testing.
The robot keeps going.
Now it's the same
robot, but here
it's got a different
kind of wheel.
These are the
electrostatic wheels
that I mentioned at
the very beginning.
So they operate at a very high
voltage, about 5000 volts,
but they are only creating
a charge differential.
So they're not powering
anything, they're just keeping
the charge between the
pad and the surface.
The reason the balloon falls
off the wall after a while
is 'cause that
charge differential
bleeds off
into the air.
So you hook up a
circuit to the balloon
after you rub it on your
head, it'll stay up there
as long as your
battery has power.
So the electrostatic
adhesives, we're partnering
with Matt Spenko at Illinois
Institute of Technology.
And these are used,
electrodes that are sort of
interstitial like this, powered
at that very high voltage.
I put one equation
in the entire talk,
'cause I felt like you
have to have one equation.
But it's a really easy one.
So it says, the force
you get from this
is a product of the
polarizability of the material,
how easy it is to create
an electric field in it,
so metals are really high,
clay and things are really low,
and the strength of
your electric field.
Of course, we got a new robot,
we gotta test it in
the zero G airplane.
So here we're showing
the first demonstrations
of zero G mobility,
I think ever.
I think this is the first robot
that's ever climbed
around in zero G.
We have had some free flyers
that are sort of
hovering and fly around.
This is the first
crawler that I know of.
So here's a spare solar panel.
This was actually an
extra from a satellite
that went up to GEO.
The slide before was mylar,
which is a common
thermal blanket material.
So the outsides of spacecraft
are covered in these
kinds of things.
Here, Christine is grappling
a one meter cylinder.
We chose one meter and aluminum
because that's the materials
of the Thor booster.
So back in the 60s and 70s
we weren't so concerned
about all the garbage
that we put up in space,
and there's hundreds of boosters
that are about that diameter,
so we're demonstrating
the ability to
grapple one of those.
It wouldn't be cost effective
to do that with all of them,
but if one of them's coming to
hit a very high value asset,
like the International
Space Station,
it'd be great to protect
yourself from that.
Here's an inchworm-style version
using gecko-like materials.
It's a lot slower,
so it was only taking
one step each parabola.
And then we're having
some fun at the end,
testing out the robot on
these curved surfaces.
So we've also done
some rapid prototyping
with a volcano bot.
This is Carolyn Parcheta.
She is bold, and I'm
terrified when we're here.
This is in Hawaii.
She came to our lab
and wanted to image
underground conduits for
fissure-style eruptions.
Now Carolyn is a volcanologist.
She has her doctorate in
Geology and Volcanology,
but she came to our lab and
asked us to build a robot
with her to image these
underground vents.
She had taken lidar and
imaged them from the surface,
but because the vents have
some sinuosity to them,
she was only to be able to get
about two or three meters deep.
Lidar only works line of sight.
I love this robot because
it's really a great example
of the methodology we try
and embrace in the lab.
We used 3D printers, motors
we already had on the shelf,
Arduino micro controllers
that we already had code for.
We basically duct taped a robot
together as fast as we could
and she and I were out
in the field in Hawaii
about four months later
testing that robot
with an Xbox Kinect
as the sensor.
Off the shelf system to map
that underground conduit.
And she had spent her Ph.D.
studying these same fissures
and had gotten that lidar data,
and even though the
robot on that first trip
only worked about 20% of the
time, we spent most of our days
in the hotel room trying to
fix it, we were able to get
some data that was
first of its kind.
Where we're imaging the fissure,
we went all the way down
to 40 meters, and we
ran out of tether.
So from three meters
to now 40 meters.
And we iterated on that, and
we went back this past spring,
and the third of fourth
version of the robot
basically worked from dusk until
dawn for two straight weeks
and we have a map now of
the entire conduit system
of one of these
fissure eruptions.
So if you look at that
data that you get back
it's generally point cloud data.
We're interested in
this for some of our
rock climbing robots, as well.
This is the kind of
thing you get back.
And we're interested in
ways to visualize that data
besides just showing
it on a computer screen
so we may try and integrate
it into some of those
virtual reality goggles
so you could actually have
a scientist be
inside that fissure
where they would never fit.
These fissures are only about
20 to 30 centimeters wide.
One more video here,
we're showing a quadrotor
that's able to land on
the side of a building.
We use a quadrotor because
we have an atmosphere here.
If you're in space, you
might have a propulsive robot
like the SPHERES robot.
We're making a new version
of that called Astrobee
up at Ames Research Center.
You could use a gripper
like this to attach yourself
to dock to the space
station or a satellite,
hang out for a while,
save your propellant,
and then take off again.
And I think this is my
last set of slides here.
I just want to voice
how fun a job this is.
What a toy shop we seem to have.
I know my garage at
home will never be
as full as my lab is
here with equipment.
So we've gotten a lot of
support from our section
as well as the JPL leadership
to make these things happen.
So this is where we
spend a lot of our time.
We also spend a lot of time
here in the machine shop.
Every once in a while, we
go to the very high-tech
facilities here at JPL to test
in a space-like environment.
And as you know,
on the good days,
I get to have a little fun
inside the zero G airplane
or have a lot of fun out in
the field with the robots.
And of course part of
NASA's mission is outreach,
and so it's always great
fun to do talks like this
and get to share our
work with the public.
So that's it.
I think a few people
in here have worked on
some of what I've shown,
so I'd ask those people
to also sort of
stand up and receive
a round of applause
along with me.
And I'll be happy to take
some questions, as well.
Thank you very much.
(audience applause)
It appears my team
is either too shy
or they didn't
wanna come tonight.
(audience laughing)
Yeah, so for questions,
if we can have you go
to the microphone
in the middle there
just so folks online can
hear the question, as well.
- Now I was just wondering
if the hooks wear out,
get blunt, become less
effective over time.
- Yeah, that's a
excellent question.
The hooks do wear out over time.
For the Asteroid
Redirect Mission,
we only have to grip
the boulder once.
Where if we fail,
we have the ability
to try two more attempts,
so they don't really
wear out over that
length of time.
The way they wear out, though,
is if you yank them
off the surface.
So they only really wear
quickly in a failure case.
If you're just gripping
and then releasing
during the normal operation,
they wear very slowly.
And we've done thousands of
cycles of that kind of grip.
But when we try and test the
max force that they hold,
they do dull over the
course of 10, 20 cycles.
Yeah, yeah.
- Question, did you think
about the possibility
of a sooty or gritty or
even oily contaminants
on the surface of some
of the aluminum objects
that the gecko adhesive
was designed to move?
- Yeah, that's a good
question, as well.
So the surface matters a
lot for the gecko adhesives.
So the smoother the better.
Because we don't
have all of that
intricate hierarchy
that the animal has,
we can only grip
pretty smooth surfaces.
And then the dirtiness
of that surface
or if it's oily or wet will
also degrade the performance.
You don't see that problem
as much with geckos
because they're able to
use a stiffer material,
and so they're more
resilient to dust
and debris and things like that.
Good news is in space,
the surfaces are generally
much cleaner than they are
in our lab, which is a mess.
(laughing) Yeah.
- A number of the
robots that climbed up
a vertical surface had
a tail, and I wonder
if there's a function to that.
- Yeah, you guys
have great questions.
A tail is very important.
If all you have is the
two wheels in the front,
the robot's gonna spin around.
So the tail reacts the moment
that keeps you
from falling back.
And tails are actually
really important
in biology, as
well, for balance.
But there's a, I didn't
show the video, but geckos-
we've worked with some
folks that do some
interesting things like
put slippery surfaces
and then make the geckos
try and climb across them.
So these are great videos.
You watch the gecko
climbing up the wall,
and then all of a
sudden it's like
it's stepped on a banana,
and it starts slipping.
And what they do at that
point, is they actually
push their tail as hard
as they can into the wall.
So they're falling backwards,
and they use the tail
as a self righting mechanism
to regain their grip.
So, yeah, tails are
really critical.
What you see on ours
are passive tails.
They're just a pole that
reacts to the moment.
I think in the future, we'd
like to make those tails active
the same way an animal's
tail is active and able to do
those kinds of fall responses
and things like that.
Yeah, other questions.
- Great talk, thank you.
- Yeah.
- So I was wondering,
what about the timelines
for these projects or
the groups of people?
Like how many work on these,
especially in the earlier
versions of rapid prototypes?
- Yeah, so the projects
will range in duration
from a few months, where
you're just trying to show
the first version of the
prototype, and to a few years,
where you really have some
higher level objectives.
The Asteroid Redirect
Mission we started
about a year and a
half ago, formally,
and that's currently
targeting to launch in 2021.
So that's a very long timeline.
We have to deliver our hardware
in a year and a half
before the actual launch.
But that gives you a
sense of the timelines.
When you're at a lower
level of development,
those prototypes can
happen very quickly.
Couple of weeks.
And you can build them
maybe one or two people.
As you get up to a
more complex robot,
the rock climbing robots,
it's a team of about five.
The asteroid grippers,
right now we're a team
of about seven, but that's
gonna grow to a peak
of about 12 or 13 of
us, I think, yeah.
Yeah.
- Can you talk a little bit
about cable tensed structures
that are pulled through
tubes as opposed to
stepper motor
actuated rigid arms?
- Yeah, sure.
So we do use cables to
actuate parts of our grippers
and other parts of the robots.
Cables are nice because they
only act in one direction.
So you can pull on
them and have tension,
but when, for
instance, those fingers
flop down on the surface,
if one flops down early,
the cable just goes slack
as opposed to a bar,
which would get jammed.
Now the downside is
that you gotta do
cable management and
routing all those cables,
making sure they're
the right length.
I have learned all my Boy
Scout knots late in life
dealing with those
kinds of systems.
So it's always an
engineering trade
between what you're trying
to have the system do
and what you're
engineering parameters are.
Another thing, maybe you
were asking about this,
is cables can be used to change
a stiffness of a
structure sometimes,
those are called
tensegrity robots.
Actually, you're human body
is a tensegrity structure.
The tendons and
muscles are in tension
keeping your stiffness different
than if you were just
standing on your bones alone.
So some folks are
working in robotics
where they're using cables
and tensioning those cables
to try and give the robot a
different level of stiffness.
In our lab, we haven't
really worked on that yet.
There's some ideas
floating around,
but we're not going down
that path right now.
- And on an extension
for the cable concept,
how are they actuated?
Is it solenoids or is it cams?
And if it is solenoids,
how would that function in
magnetically active environments
like the Van Allen belt?
- So none of what you
saw today was a solenoid.
In prototyping, a lot of
times we use servo motors
or just brushed DC motors.
A lot of times, as
well, we're trying to do
underactuation so when
those carriages lift up,
that's one motor that's
powering all 16 of those, right?
We're just pulling
on a plate that has
all of those cables
attached to it.
In flight, a lot of times
we use brushless DC motors
because the brushes
can create debris
and don't work quite
as well in vacuum.
So we use those as
well, sometimes.
It's sort of a-
each job requires maybe a
different consideration.
Yeah.
- Thanks.
- It's too tall for me, okay.
Hi, this is very exciting,
so thank you for this talk.
I was wondering what
the current use rate
of 3D printing is for you
guys, and is there a plan
or a roadmap to increase
that to a certain percentage,
whether it be for
efficiency or just
ease of building maybe
what doesn't exist?
- Yeah, so I would say-
Well we have, let's see,
we've gone through probably
12 or 15 different 3D printers
in the last five years or so.
We bring in some of the low
cost hobby kind of grade ones
that we use for quick,
dirty prototypes,
and we turn our
students loose on those.
We also have some high-end
printers that we call them
the Ferrari because the price
tag is kind of equivalent.
But across the board, those
printers run every day for us.
So at times during the summer,
which is our busiest season,
we haves queues of people
waiting to print parts.
So in a prototyping phase,
they're in use constantly.
And we've tried to
open up that lab space
to the broader JPL
community, as well.
So we have people from
all different sections,
all different departments
coming by to print parts
because they have
a need for them.
So the adoption rate
has been really quick.
I think it's gonna
continue to grow.
One area that we haven't
really moved into yet
but I think is coming
is metal 3D printing.
So we have filament
style printers,
we have liquid UV resin
kinds of printers,
and I think the metal
printers are coming next.
We've outsourced some parts.
We use local shops and
vendors all the time, as well.
So we've had some titanium
printed parts that we've used,
but I think JPL is
gonna get on board
and get some of our own
machines there soon, as well.
People are actually looking
into flying 3D printed parts
as part of the spacecraft.
So it makes a lot of sense,
and I think it's gonna happen.
- Thank you.
- It looked like a number of
your robots were autonomous,
weren't any cables
attached or anything.
Could you talk briefly
about what kind of
controllers they have on
board to have direction
and move the limbs
and all of that?
- Yeah, so autonomy is
an interesting thing.
We don't think of
autonomy as on or off,
we think of it as
a slider between
fully teleoperated
and fully autonomous.
And so on some of the robots,
that slider's kind
of in the middle.
If you're climbing up a
wall, and you're trying
to steer looking at a
camera, turns out the wall
looks the same whether
you're 15 degrees to the left
or 15 degrees to the right.
So what we do is
we augment the user
by steering to match the
gravity vector, right?
So this is sort of autonomy,
but it's also still being
controlled by an operator.
On the further side for
the rock climbing robots,
we are trying to make
that much more autonomous
where we give it waypoints that
are maybe a few meters ahead
of where it is, and it
decides how to move its limbs
and where the good
places to grip are.
Turns out that a person
trying to sort of joystick
a seven degree of freedom limb
is actually not very good.
It's too complex for you
to work out in your head
which motor has to
move at which time.
And you don't have
enough buttons
on the controller
to do it, anyways.
And so we try and use
a lot more autonomy,
move that slider closer to
a fully autonomous state
for some of the rock
climbing robots.
- And what do you use on board
for a processing satellite,
do we know?
- So, no, so the
rock climbing robot
right now has two
brains, if you will.
It's got a low brain
that's a PC/104 stack.
So that's a bunch of cards.
It's actually pretty old
electronics technology.
And then it has an Intel NUC,
which is a much more powerful
computer that's doing the higher
level computer vision work
and the trajectory
generation, and then those two
have to talk to each other.
So the lower brain handles
make the motor spin,
and that Intel computer handles
the where do I put my foot
and how do I move
all of my joints.
- Thank you.
- Sure.
- Hi.
- Hello.
- So I have questions about
the adhesive gecko robots.
- Sure.
- So you guys are
planning to deploy that on
a mission to Mars, right?
So my question is that
the weathers on Mars
are much harsher
than it is here on Earth,
have you guys thought about
something like
how to tackle that
when it hit a storm or
something like that?
- Yeah, so the
environment on Mars
is obviously very extreme.
It's funny that our group name
is Extreme Environment Robotics.
You might think
that the entire lab
is really doing extreme
environment robotics.
So it's a consideration.
In the prototyping
phase, we haven't really
been too concerned about
the thermal environment
or protecting ourselves
from dust and debris,
but as that robot
matures, we would bring in
all of those folks from
JPL who are really expert
at managing the cold
temperatures and the
hot temperatures and
managing the dust storms
and some of those
sorts of things.
And I don't think there's
any critical limitations
for the rock climbing
robots to operate
on the surface of Mars.
The gecko adhesives are
really tailored more
to smooth surfaces, so we
wouldn't use those on Mars.
We'd use the gecko
adhesives in orbit
to grapple satellites
and operate maybe
on the sort of carrier ship
that would go back and forth
between Mars and
Earth but not actually
on the surface where
it's dirty and rough.
- Alright, thank you.
- You're welcome.
I think we have a couple
questions from online, maybe.
And these have been screened,
so these are the
best ones, I think.
(audience laughing)
The question here is what are
the major challenges in moving
the grippers from field
tests to space flight tests?
That's a great question.
Some of the challenges
are technical
like figuring out
how to make it robust
across all of the
different rock types.
So it's easy when you're
developing something in the lab
to kind of design it to work on
whatever you have in the lab.
You take it out into the
field and you realize,
oh, this rock is actually
a little different.
We're going to have to go
back and fix some things.
So some of the technical
challenges are in making it
robust, making sure it
doesn't break over time.
But some of the other
challenges to moving
from the lab to space flight
are actually programmatic.
You need to be in the right
place at the right time,
so if you're developing a
technology that's really tuned
for Venus, and the next
mission is going to Mars,
you've got a mismatch
there, and so there's always
a little bit of awareness and
strategy that NASA and JPL
is trying to stay on top of
to make sure we're developing
the right technologies
for the next missions.
So some of the
challenges can be of that
more personal or
non-technical variety.
I guess the other one,
which is a big driver,
is testing, the costs of
doing environmental testing
and really validating your
technology can be very high.
So to do that on an R&D budget
can be a real challenge.
And sometimes there's a mismatch
between what a mission
is willing to pay for
and what the technology
program is willing to pay for
where you have to try and
prove that you're ready
for the mission, but in
order to do that testing,
you need the dollars that are
associated with the mission.
So sometimes, it's trying to
scrap together a story that
really proves that it's gonna
work in that environment.
So the second question here is
are AI and machine learning
technologies in use here?
And if so, how?
So the answer, AI
and machine learning,
they are definitely
in use here at JPL.
In the robots I
showed you here today,
we're not really doing much
machine learning or AI.
The one exception to that,
is we're trying to train
the rock climbing robot on
what is a good place to grip,
and so we've just started
collecting lots and lots
of 3D models of different rock
faces, and we're, by hand,
highlighting these are
good places to grip,
these are bad places to grip,
and then we're gonna feed
that into a program that
will learn, hopefully,
from those examples where
those good places to grip are.
That's work that's just
getting under way now.
But there's a lot more complex
machine learning and AI
that's happening in
other projects at JPL.
So I'd encourage you to go
to the JPL Robotics website,
and there's lots of videos
of some other robots
that really emphasize
those technologies.
So that's it, and I'll stick
around up front if people have-
well, we'll take one
more question, I guess.
- Thank you.
- Go ahead.
- I appreciate it.
On the ARM project, when you
bring the boulder off the comet
and you bring it to the
Moon and put it in orbit
around the Moon, you said that
you were gonna let companies
possibly go up there
and practice mining
and that sort of thing.
Is that something that
we'd be able to see
through a telescope?
I know you said it's as
big as a SUV, possibly,
in orbit around the Moon,
and I was just wondering
if that would be like
something we'd be able to see,
and how big is the orbit,
and how long would
it take to go around?
- Yeah, so after we pull the
boulder from the asteroid,
we'll put it in
a, what's called a
retrograde orbit around the
Moon, so it's very stable.
And it'll be up there
for hundreds of years.
Now, I don't think
it'll be large enough
to see with most telescopes.
I think you might be able
to see a point source
that, yeah, there's a signal or
certainly we're going to be
talking to the spacecraft,
but I don't think,
optically, you're probably
going to be able to see that.
But that's my 90%
confidence answer,
I'm not for sure on that.
- [Man] Put a reflector on it.
- Yeah.
(audience laughing)
But you'll get great videos
when the crew come and dock
with that spacecraft and the
boulder, and we'll probably see
all of that happening in near
real time down here on Earth.
So that'll be very exciting.
Thank you again for
coming, it was my pleasure.
(audience applause)
Have a good evening.
(uplifting, enchanted music)
