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RoboRoach

Swim Like a Fish

Body Builders

Robots Have Feelings, Too

Go, Team!

Viewer Challenge
in the classroom
TEACHING GUIDES


Natural Born Robots:
"Body Builders"


Conventional programmed robots can't think for themselves. The real challenge for robot builders and engineers is designing autonomous robots that will develop and evolve minds of their own. Meet Cog, probably the best example of an intelligent robot. His creator wants to build a robot that really thinks, reasons and understands. Cog's inspiration for learning? Children.

Curriculum Links
National Science Education Standards
Activity: Get a Grip
Think About It!




CURRICULUM LINKS


BIOLOGY/
LIFE SCIENCE


gait, muscular system, walking

COMPUTER SCIENCE

AI, programming

PHYSICAL SCIENCE

biomechanics, simple machines

TECHNOLOGY

robotics

(Please visit the Subject-Area Search feature on this website for related Frontiers shows and activities!)




NATIONAL SCIENCE EDUCATION STANDARDS

SCIENCE AS INQUIRY / LIFE SCIENCE
5-8: Structure and Function in Living Systems; Regulation and Behavior; Diversity and Adaptations of Organisms
9-12: Biological Evolution; Matter, Energy and Organization in Living Systems; Behavior of Organisms
SCIENCE & TECHNOLOGY
5-8, 9-12: Abilities of Technological Design; Understandings About Science and Technology
SCIENCE IN PERSONAL & SOCIAL PERSPECTIVES
5-8: Science and Technology in Society
9-12: Science and Technology in Local, National and Global Challenges
HISTORY & NATURE OF SCIENCE
5-8, 9-12: Science as a Human Endeavor




ACTIVITY: GET A GRIP: BUILD A MODEL

Building robots like Cog requires years of work by teams of scientists. Cog is an extremely complex machine that has been evolving over the years, thanks to creator Rodney Brooks, director of MIT's Artificial Intelligence Lab.

Robotic arms perform many tasks in the real world -- lifting, grasping, grabbing, probing and more. While not the fantastic robots of the movies, robotic arms emulate an authentically amazing design -- the human arm.

Before you can build a model, you need to find out how your arm works and what muscles are involved. You'll need to identify and label specific muscles and bones used to lift a ball from a resting position to your shoulder and back down again.

  • To begin, place a ball or other object in your hand and hold your arm straight down at your side.

  • Place a finger on the muscle and bones to feel how they move.

  • Raise your hand until your arm is at a 90-degree angle.

  • Now raise your hand toward your shoulder and then lower it back down.

  • Consult an anatomy book or online resources to identify the muscles and bones, so you can build a simplified model of a human arm.

  • You'll use your model as the starting point for designing and building a robotic version.

For animated comparisons of human and robotic arms, see http://www.thetech.org/exhibits_events/online/robots/teaser/. Visit the MIT Cog Shop at http://www.ai.mit.edu/projects/humanoid-robotics-group/cog/cog.html.




MATERIALS

  1. craft sticks (2 per model)

  2. rubber bands (2 large and 2 small per model)

  3. scissors or other tool to cut notches in craft sticks

NOTE: You may wish to use other materials to build a more complex model.

human arm




PROCEDURE
  • Use anatomy resources and the materials above to make a simple model of the arm to show how it lifts a ball toward the shoulder. Work individually or in pairs.

  • To simplify things, have only two "bones" in your model. One will represent the scapula and humerus; the other will represent the radius and ulna. (Build a more complex model if desired.)

  • Wrap the two small rubber bands around the craft sticks to secure the bones at the elbow joint but allow the joint to move.

  • Cut two small notches in each craft stick to represent the origin and insertion of each muscle. Using rubber bands to represent muscles, attach two muscles, the biceps and triceps, to your model arm.

  • Make sure your model works. That is, when you pull on a muscle (contract it), the arm moves in the way the real arm would.

  • Label the parts of your model.





THINK ABOUT IT!

Nature has had millions of years to solve problems, such as how to make an arm that works as a lever. Robot makers find that the more they try to copy nature's designs, the more they need to understand human anatomy. Compare your model to anatomical design as you answer the following:

  • When pulled, rubber bands stretch and store energy, then return to a relaxed shape. How does this action, shown by the rubber bands in your model, compare to the way real muscles work?

  • The elbow joint in your model had to be held together but still move. How does the human body hold joints together to allow them to move?






 

Scientific American Frontiers
Fall 1990 to Spring 2000
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