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Wallbot’s Possession of Balls


8800X
13-May-2020

SG8: Robots may not have greater-than-momentary Possession of more than three (3) Balls of its opposing Alliance’s color at once. When two Robots from the same Alliance are working in tandem and blocking Balls, those Robots may not Possess a total of more than six (6) Balls of its opposing Alliance’s color at once.

SG8 establishes a Robot may not have Possession of more than 3 of the opposing alliance’s balls at one time. The definition of Possession is the following:

Possession – A Robot is considered to be Possession a Ball if a Ball is in an unscored position and either of the following criteria are met:

• The Robot is carrying, holding or controlling the movement of a Ball such that if the Robot changes direction, the Ball will move with the Robot. Pushing/plowing Balls is not considered Possession, however using concave portions of your Robot to control the movement of Balls is considered Possession.

• The Robot is blocking the opposing Robot’s access to Balls that are located between Goals along the field perimeter.* Blocking access to Balls is considered Possessing those Balls only if the opposing Robot is attempting to make contact with those Balls from close range* AND those Balls are at least partially within the width of the Goals between the Goals. Robots on the same Alliance working in tandem to block access to Balls would share the Possession of the Balls. See <SG8> for Possession limits.

Emphasis added. A wallbot that has sectioned off a portion of the field does not meet the criteria for possession in the first bullet point as the wallbot (assuming it is stationary) is not carrying, holding, or controlling the movement of a ball. The focus of this question centers around the second bullet point.

There are two conditions under the second point. The “and” qualifier necessitates that both conditions must be met in order to be considered in possession of a ball.

The first condition is that the opposing robot has to be attempting to make contact with a ball from close range and the second is that a ball is partially between the width of two goals along the field perimeter. The second condition is easy to interpret. The first condition is likely up to the discretion of the Head Referee as to what is considered “from close range.” Please review the following scenarios below so that there is precedent for Head Referees to base their decisions upon.

Scenario 1

img An image of scenario 1 can be found at the bottom of this post. A blue robot has deployed a stationary wall in the corner. The wall is tall enough so that no robot can reach over the wall and make contact with balls. A red ball is directly behind the blue wall. A red robot is directly on the other side of the wallbot. The Red robot is attempting to make contact with the red ball and is within close range of the red ball. However, the red ball is clearly not between the width of the goals along the field perimeter. Therefore, the blue robot is not in possession of the red ball. Is this interpretation of scenario 1 correct?

Scenario 2

img An image of scenario 2 can be found at the bottom of this post. A blue robot has deployed a stationary wall in the corner. The wall is tall enough so that no robot can reach over the wall and make contact with balls. A red ball is clearly between the width of two goals along the field perimeter. A red robot is on the other side of the wall but is at least a full tile’s length away from the ball. The Red robot is attempting to make contact with the red ball. However, the red robot is not within close range of the red ball. Therefore, the blue robot is not in possession of the red ball. Is this interpretation of scenario 2 correct?

Scenario 3

img An image of scenario 3 can be found at the bottom of this post. A blue robot has deployed a stationary wall in the corner. The wall is tall enough so that no robot can reach over the wall and make contact with balls. A red ball is clearly between the width of two goals along the field perimeter and a red robot is directly on the other side of the wall. The red robot is attempting to make contact with the red ball. Even though the red robot is unsuccessful in making contact with the red ball, it is within close range and attempting to make contact. Therefore, the blue robot is in possession of the red ball as both conditions are met. Is this interpretation of scenario 3 correct?

Answered by Game Design Committee

Thank you for the detailed question, and for your patience while we reviewed the rules in question. <SG8> and the definition of Possession have been modified in the August 17th Game Manual Update to address this confusion. If more clarification is still needed, please feel free to rephrase and re-submit.