Although bionic arms have been
around for a few years, the idea of a mind-controlled robotic limb
is still pretty amazing! The latest story of an amputee using
a high-tech prosthetic leg provides the perfect opportunity to
introduce your students to the science behind robotics.
Researchers from the Rehabilitation
Institute of Chicago have taken a big step forward (horrible pun -
sorry!) by developing a new generation of prosthetic legs.
They've equipped amputee Zac Vawter, who lost his leg in a
motorbike accident, with a motorised, computerised limb that mimics
the movement of a real knee, ankle and foot.
Zac Vawter becomes the first
person with a bionic leg to climb one
of the world's tallest skyscrapers (c) Associated Press
Photos
In order to test the new leg, Mr
Vawter set off on a challenging 103 storey stair-climb to the top
of one of Chicago's tallest skyscrapers.
Have a look at this video to see
the bionic leg in action:
As the
NY Daily News reported, testing a robotic leg in this way isn't
entirely safe - if it had failed then Zac Vawter could have tumbled
back down the 2,100 stairs he had been walking up.
Thankfully, the public
demonstration at the annual stair-climbing charity event called
"SkyRise Chicago" was a roaring success. Vawter told
reporters, "Everything went great, the prosthetic leg did its part,
and I did my part."
What's the science behind
the headline?
Bionics (also called biomimetics -
imitating life) combines:
- biology
- neurology
- physics
- electronics
- engineering
The muscles in the human body are
controlled by electrical impulses sent from the brain and spinal
column (for more details read our article about
Frankenstein's monster and the real life experiments that
inspired the story for more details).
Robotic limbs are designed to
detect these electrical impulses from the muscles in the leg or arm
of the amputee, and respond to them with the appropriate
movement.
In the case of Zac Vawter, surgeons
connected his nerves that would have controlled his lower leg to
his hamstrings. The hamstrings are the tendons just above the
back of the knee and are part of the group of muscles that bend our
knees.
With the nerves attached in this
way, the electrical impulses that Zac Vawter's brain sent when he
thought about climbing the stairs were detected by the bionic
leg. The motors, belts and chains in his leg then
synchronized the movements of its ankle and knee.
This amazing breakthrough is part
of an $8 million project funded by the U.S. Department of Defense
which involves four major US universities, including the
Massachusetts Institute of Technology (MIT).
It is hoped that the project will
lead the production of mind-controlled prosthetic legs that will
change the lives of many lower limb amputees from injured soldiers
to accident victims.
For some ideas of how to include
robotics in your science lessons have a look at the following
sites:
If you know of any other resources,
lesson plans, videos or ideas please let us know using the contact form and we can add them to the
site.