[Music]
someday in the near future you might be
wandering around town at night
when out of the blue you'll stumble
across a robot if that happens maybe you
shouldn't be too surprised not so long
ago robots were mostly found in the
realms of science fiction
today they're vacuuming floors building
cars and even roaming around the surface
of mars
robots are still pretty far from having
a human level capacity of intelligence
or even dexterity for that matter
but they're already a big part of many
branches of engineering in the u.s over
100
000 robots have been added to factory
floors since 2010
knowing exactly what robots are what
they can do and how they work is more
important than you might think
because soon they might be living among
us
the classic picture of a robot is
something with human-like intelligence
and maybe even a humanoid appearance but
like so much else real-life robots
aren't much like what you usually see on
tv robots come in all shapes and sizes
and they can be built very differently
depending on what they're used for for
example
some of the robots used in mining are
made from a camera mounted on a small
chassis with wheels
that allows them to enter and inspect
mine shafts and even retrieve leftover
material
from places it's hard to get people in
and out of meanwhile in medicine
specialized robotic arms with a bit of
human assistance
can perform precise surgeries through
the tiniest incisions there's also a
difference between robotics and
artificial intelligence or ai
which people sometimes confuse while
some of the concepts are similar
robotics deals with a specific set of
ideas although it does borrow a few from
ai
ai deals broadly with the goal of
automating decision making for complex
tasks
the kind you can't write a simple set of
rules for that could be everything from
playing chess
to driving cars right now ai systems
tend to have very narrow goals
but the holy grail of ai is to develop a
system that can make intelligent
decisions
about any sort of task using different
sources of information
our focus will be on robots which are
designed for more specific purposes in
the physical world
in engineering terms a robot is a
machine designed to interact with its
environment
make an appropriate decision based on
those surroundings and then carry out
the jobs related to its goal
all automatically which means a true
robot doesn't require a human
controlling exactly what it does
in general the field of robotics also
deals with machines that do
all of the same things but might require
a human operator to carry out some tasks
whether fully automatic or not
virtually all robots have a few features
in common first
robots are machines made from materials
that occupy physical space
so they're more than just lines of
computer code that's one of the key
features that distinguishes them from ai
although computer engineering is
important for robots as well second
most robots have some way of sensing
features of their environment
usually by measuring light sound or
force feedback they can then use that
information to make a decision about
what to do next
depending on what they're designed for
the tasks robots are built for tend to
be complex
requiring a sequence of different
motions so an automatic door that opens
or shuts in response to whether you
stand in front of a sensor wouldn't be
considered a robot
the tasks that robots handle are more
sophisticated
like welding two intricately shaped
pieces of metal together third
to interpret the signals they receive
from their environment and coordinate
some sort of response
robots have computers built somewhere
into their design these work just like
any computer
taking inputs and delivering outputs but
unlike most ordinary software
the software on a robot's computer
generates electrical signals that are
directly passed onto the robot's
hardware
instead of just changing information in
a file or on a screen that also requires
a power source
one option is to physically hook up to
the power grid using wires and a socket
for example the 2013 version of the
atlas robot
developed by robotics company boston
dynamics had a humanoid design that
could walk and carry objects
much like humans do to operate atlas
relied on a cable that tethered it to a
power supply but tethering robots like
this limits how far they can move
and interferes with the robot's mobility
so to let atlas move around
more freely engineers installed a
battery on the robot structure so it
could power itself
unfortunately the materials of a battery
tend to be rather heavy
which posed its own challenges if we
don't want robots like these toppling
over all the time
it takes a bit of mechanical engineering
know-how to work out where to position
the battery with respect to the robot's
center of mass
you might need some chemical engineering
in the design of the battery too in the
case of atlas
engineers gave it a hydraulic pump in
its torso to help it support the extra
weight of its lithium-ion battery and
now
only a few years later it can do
backflips and parkour more generally
some electrical engineering also has to
go into wiring the signals from the
computer program
to the robot's physical parts which
brings us to another common feature of
robots
they have mechanical parts like grips or
wheels for carrying out whatever
physical tasks they need to in their
environments that might be turning a
lever picking up an object or just
moving somewhere else and there are some
unique challenges to designing those
parts consider a robot designed to pick
fruit from trees
from an engineering perspective it needs
some fundamental qualities
the ability to recognize fruits and
distinguish them from the rest of the
plant
navigate its environment to move toward
the fruits that need picking
and then to pick them and put them into
a container let's start with how it
moves
a fairly basic requirement for lots of
robots like with the mining robot you
could simply put some standard axles
with wheels on the bottom of your robot
and attach them to a motor like on a car
that would be fine if the robot was
going to be operating mostly on smooth
even surfaces
like roads or factory floors but most
fruits are grown outdoors
sometimes in rough terrain and difficult
environments so you might need to design
adjustable wheels that change height
independently
or add treads to overcome small bumps
like on a tank the problem with wheels
is that they're not very good at
overcoming large obstacles if there's a
fallen branch or a boulder blocking the
way
the robot needs to be able to climb over
it giving the robot legs could allow it
to jump
but that has its own problems robots
with legs tend to fall down
a lot as the team at boston dynamics
found when designing atlas
programming a robot's computer to
interpret its environment
while handling the dynamics of all those
mechanical parts is trickier than it
seems
it really makes you appreciate what a
good job your brain is doing of course
to actually make sense of its
environment and find fruit
the robot will need sensors devices that
measure physical characteristics and
translate them
into a signal to find apples for example
the robot might have an array of light
sensitive semiconductors
like the kind that make up light
capturing pixels in a digital camera
to scan an orchard but the information
sent by the camera sensor is interpreted
by the computer as an array of coloured
pixels
that don't mean an awful lot on their
own the average person can take one
glance at a curvy shape of reddish
pixels
and instantly recognize it as an apple
for a computer
that requires a fairly sophisticated
visual algorithm what's more
people are good at seeing where the
edges of objects are and interpreting
the relationship they have to their
environment
and how far away they are you know an
apple that looks very small is most
likely one that's very far away
but even a relatively smart computer
that can recognize apples
might not know whether it's a tiny apple
only a few centimeters away
or an enormous apple a few kilometers
away which would affect whether the
computer's programming tells it to pick
the apple or not
all of these issues are what are known
as computer vision problems
computer vision deals with how to train
software to take the input data from
images or video
like the kind that are delivered from
digital cameras and interpret it the way
a human would
even once it's found in apple and moved
itself close to it the fruit picker is
going to need mechanical parts to
actually
pick the fruit the main mechanical parts
used by most industrial robots are
called
actuators and effectors actuators are
like robots muscles
they convert stored energy into movement
one popular type are electrical
actuators
electrical motors that turn wheels or
gears to rotate the robot's connected
parts with respect to one another
these are the sorts of mechanisms that
would extend the robot's arm
toward or away from a particular branch
linear actuators can achieve this by
using a motor
to extend the part up and down a thread
like a nut on a bolt
they can also use compressed fluids like
air or oil to extend a part outwards
then use a motor to compress the fluid
and bring the parts back when needed
effectors meanwhile the parts that
actually have an effect on the robot's
environment
basically the robot's hands to deal with
the irregular shapes of different fruits
you could have what's called a vacuum
grip that can suck up
large objects and hold them in place but
most of the focus on building robots has
been on mechanical effectors
the kind that rely on tactile feedback
and manipulating
in other words they give the robot an
artificial sense of touch
perhaps with force sensitive electrodes
on the affected surface
having a sense of feedback is important
for applying the right amount of
pressure
otherwise the apple might slip out of
the robot's grip or be crushed into a
pulp to achieve this
the effector might be a simple two-part
claw or something more sophisticated
with many parts modelled on a human hand
picking fruit is the kind of job that
robots could accomplish at scale
much more easily than humans freeing
them to work on other aspects of farming
but robotics isn't just aimed at saving
labor
robots can also be used in environments
that are far too dangerous to send
humans into bomb disposal robots which
are actually more like drones
are operated by humans to find explosive
devices
and disarm them from a safe distance in
the future fully automated robots might
find uses in other harsh environments
like the deep sea and space but it's
likely that the place robots will have
the most impact
won't be in the jobs they do instead of
humans but the ones they do
alongside them features of robotics are
already making their way into healthcare
like in the development of prosthetic
limbs but in situations like surgery or
disaster rescue operations
a combination of human smarts and
purpose-built robotic strength
could create safer more efficient and
totally new ways of doing things so like
many engineering tools
robots will work best when they weave
into our existing methods
working alongside us to accomplish our
goals robots might be the future but
it's a far cry from the terminator in
this episode we looked at robots and the
engineering principles of robots
we learned how robots use sensors to
interpret their environment how
actuators and effectors allow a robot to
manipulate the objects around it to
accomplish a task
and how computers coordinate the efforts
of the two
crash course engineering is produced in
association with pbs digital studios
which also produces it's okay to be
smart a show all about our curious
universe
and the science that makes it possible
hosted by dr joe hanson
check it out at the link in the
description crash course is a complexity
production
and this episode was filmed in the dr
cheryl c kinney studio
with the help of these wonderful people
and our amazing graphics team
is thoughtcafe