VEX Center of Gravity

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VEX Center of Gravity
J.M. Gabrielse
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Center of Gravity

• The center of gravity is the average mass and
  position of all the pieces that make up a robot.

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Robots tip over all the time!
Build your robot so the center of gravity stays
between the wheel axles and your robot wont tip
over.
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Find the Center of Gravity

• Hang any object from a string
• The object will rotate until the center of
  gravity lines up with the string.
• Hang the robot from a string and mark the line.
• Tie the string to a different points and repeat.
• The center of gravity is where the lines cross.

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The Center of GravityIs Where the Lines Cross
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Tipping

• Robots tip if the center of gravity isnt between
  the wheels.

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Robot Arm

• Pick something up and the center of gravity moves

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Robot Tips

• Keep heavy items
• close to the ground
• in the middle of the robot
• The protobots battery and arm balance each other
  out to keep the center of gravity in the center
  of the robot.

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Your Turn

• Where is the center of gravity?
• What happens to a robot if the center of gravity
  isnt between the wheels?
• How can you make a robot less tippy?

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Resources

• Inventors Guide 27 - 211

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Resources

• http//www.education.rec.ri.cmu.edu/roboticscurric
  ulum/vex_online/lessons/mechanics/center_of_mass/m
  echanics_center_of_mass.html
• Inventors Guide 27 - 211