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Center of Gravity

VEX IQ Curriculum - Key Concepts


Center of Gravity

Center of Gravity is the place in a system or body (such as a robot) where the weight is evenly distributed and all sides are in balance. An example of center of gravity is the middle of a seesaw when it is balanced.

VEX IQ Curriculum Center of Gravity
Figure 1. Approximate Center of Gravity on a seesaw.

You can think of a robot’s center of gravity as the “center position” of all the weight on the robot. Because Center of Gravity uses both weight and position, heavier objects have a greater effect than lighter ones in determining where the center of gravity is. For example, if your robot can collect, hold, and/or manipulate objects, those objects change the center of gravity as they are being manipulated because they add weight.


Figure 2. Approximate Center of Gravity on a robot with and without a cube.

Likewise, pieces that are farther out have a greater effect than pieces that are near the middle of the robot. So, if your robot has an arm that lifts and/or reaches, its center of gravity changes with that movement.


Figure 3. Approximate Center of Gravity when the robot arm is down and in versus up and out.