Structure

Hardware used to attach parts to each other.

Metal Material

While being a seemingly insignificant factor, choice in metal material can have a drastic impact on a robot's performance. There are two types of metal used in VEX products:

Characteristics

Heavier Material	Lighter Material
More Rigid and Durable	Easier to Bend and Break
Appears Darker and more Reflective	Appears Lighter and flat

On the Robot

Due to its lighter weight, aluminum should be used in subsystems that need to be kept as light as possible, such as lifts and game piece manipulators.

Steel is commonly used in areas where weight is less of a concern, or when a subsystem needs to be made heavier. In the event of a drive ratio favoring torque, a robot can be made heavier to help prevent being pushed by other robots.

As a general rule, however, aluminum should be used in the vast majority of places. Having a heavier robot, unless designed to be so, can be detrimental, and using aluminum instead of steel helps to drastically reduce the weight of a robot or subsystem.