<R4>
Robots must fit within an 18” x 18” x 18” volume. Compliance with this rule must be checked using the official VEX Robotics On-Field Robot Expansion Sizing Tool: https://www.vexrobotics.com/276-5942.html. Any restraints used to maintain starting size (i.e., zip ties, rubber bands, etc.) must remain attached to the Robot for the duration of the Match, per <G6>. For the purposes of this rule, it can be assumed that Robots will be inspected and begin each Match on a flat standard foam field tile. The official sizing tool is intentionally manufactured with a slightly oversized tolerance. Therefore, any contact with the sizing tool (i.e., a “paper test”) while being measured should be considered a clear indication that a Robot is outside of the permitted size. This tolerance also provides a slight “leeway” for minor protrusions, such as screw heads or zip ties. Other tools, such as custom sizing boxes or the legacy non-expanding VEX Sizing Tool (276-2086), may be used for informal checks. However, in the event of a conflict or “close call,” a check with the official On-Field Robot Expansion Sizing Tool takes precedence. Although it is not required by <R4>, events may also choose to check that any possible Robot expansion satisfies the requirements of <SG2> during inspection. The intent of this check is to help Teams identify any potential Violation risks before their Matches.