Can Prosthetics Outperform Real Limbs?

I was a very strange child.

I would sit in the basement,

no sound, silence,

I'd just sit there and rock.

I'd do this for hours and hours and hours.

I think my parents thought I was insane,

but what I was doing is imagining futures,

imagining what life could be.

The next step in human evolution

may not be biological, but technological,

by merging ourselves with machines

that augment and enhance

our physical and perceived realities.

But this is no small feat.

The human form is a product of billions or years

of natural selection.

That's why innovators like Hugh Herr

are actually looking to nature for inspiration

to bridge the gap between man and machine.

When I was 17

with my climbing partner Jeff Batzer

we ice climbed Huntington's Ravine

on Mount Washington.

We got disoriented in a complete blizzard

and spent the next several days

trying to get ourselves out to civilization.

We made it within a few miles of a roadway

and we couldn't walk.

Our lower limbs were completely frost-bitten,

completely numb.

Luckily, someone was out snowshoeing,

saw human tracks,

and we were plucked from the mountain via helicopter.

Then I spent months in the hospital.

Gangrene had set in,

was slowly making its way up my body.

It was clear that amputation was necessary.

About 12 months after my limbs were amputated

I was climbing at the same level

as I had before the accident.

People started to get nervous.

Then I exceeded that level

and started to climb walls

that no one ever climbed before.

Then I became a threat.

That happened over night.

Some of my climbing colleagues

actually threatened to cut their own legs off

to achieve the same unfair advantage as me.

No one actually did it.

The fact that I could design my body part

and exceed what I had achieved before,

and even exceed what nature intended,

was very inspiring.

I realised the technology has the power to heal,

to rehabilitate and to even extend human experience

and human capability.

That set me on this trajectory of tinkering,

of designing, climbing and then going back to the shop,

and then whittling and carving and machining.

My closet looked really funny.

You didn't see shoes,

you saw these bizarre limbs and feet everywhere.

So, what sets Hugh's legs apart from the rest?

Most prosthetic legs are passive.

As a result,

amputees have to use about 20 percent more energy

when walking with their prosthetic leg.

Hugh and his team

studied how our leg and ankle naturally work

to create their bionic counterparts.

Our key strategy in the design of bionic appendages

is to look into nature.

We studied how the calf muscle works for example

and how the calf muscle is controlled by the spinal cord

using neural reflexes.

We programmed that capability on the small computers

that are underneath the shell in the bionic limb,

so that when I walk at different speeds

and different terrains

it's constantly updating

the stiffness and power it's providing me.

[Derek] The motor mimics our calf muscles,

adding positive force to the prosthesis.

That propels the body forward.

This is especially helpful for walking up ramps and stairs.

Even though the limb is made of titanium and carbon

and all these synthetic materials,

it moves as if it's made of flesh and bone.

The value of closely respecting the biophysics

is that when we fit this prosthesis to a human body

there's often no training

because the human body remembers how to walk.

Oh my God.

I can't believe it.

(laughing)

It's just like I've got a real leg.

That's the value of this biomimetic design approach.

We built our first foot-ankle in 2002.

It's been a long, iterated process.

Probably 30 fundamentally different designs

that led to the bionic limb as it exists today.

We're studying how the tissues in this part of my body

how stiff they are,

we're studying how the skin moves.

We then 3D print structures

that emulate those tissue properties.

It looks like a topographical map

of your residual limb.

It makes for one of the most comfortable

sockets available today.

Beside the physical attachment to the prosthesis,

Hugh's team is working on a way

to control bionic limbs more naturally.

They've developed legs with EMG sensors

that measure and decode the electrical impulses

in the muscles of the residual limb

and then translate that into movement.

Thus, the user only has to think about moving their leg

to activate the bionic limb.

I have the condition that my limbs are amputated,

but that condition because of great technology

I have the quality of life that I seek.

Extending that story across all of humanity

one can imagine a world

in which technology's so remarkably great

that we can eliminate disability.

I believe that will happen in this century.

The twilight years of this century,

there will be no disability in the world.

[Derek] Check out more episodes of Cyborg Nation

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