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Official Q&A: VRC 2023-2024: Over Under

Usage Guidelines All Questions

[Possession] To what extent would a concave space be considered possession/control of a Triball? What is "momentary" possession?


Kayla Ho (Event Partner)
9-Aug-2023

The primary questions for clarification are:

  1. To what extent would controlling a Triball be considered possession/control of a Triball?
  2. What is "considered" momentary - a bump, one second...? How is this quantified?

The below is supporting material for the first question.

In the Game Manual, the definition of Possession is as follows: "A Robot / Triball status. A Robot is considered to be in Possession of a Triball if the Robot is carrying, holding, or** controlling the movement of a Triball such that if the Robot changes direction, the Triball will move with the Robot**. Therefore, pushing/plowing Triballs is not considered Possession; however, using concave portions of a Robot to control the movement of Triballs is considered Possession."

Per <SG7>, Robots many not "have greater-than-momentary Possession of more than one Triball at once".

Per the definition and SG7, how "controlling the movement of a Triball if the Robot changes direction and the Triball moves with it" be measured or determined?

For example, would the following areas indicated in red be considered possession since the spaces are concave and the Triballs would potentially move with the Robot when it is in motion?

A) The below indicated with a red arrow is a concave space, the Triball would move with the robot when it changes direction (e.g. turns), but would this be considered possession?img

B) This below indicated with a red arrow is also concave and also permits the Robot to control the movement of the Triball. Is this considered possession? img

C) The below rectangle indicated with a red box is a concave space. Would this be considered possesion? How deep into a Robot must a Triball be to be considered possession? In the case where a Robot can strafe/move laterally, would it be considered possession if the Robot is plowing in addition to holding a Triball in a concave space? img

D) The below image is a giant funnel that would control the movement of the Triballs, but at some point the Triballs would fall out if the Robot is turning. Would this be considered possession? img

E) The below images are more likely implementations that we might see. The right side design would have more control than the left given the geometry. How much control can have over a Triball(s) before it is considered Possession of more than one? img

Answered by committee
5-Oct-2023

We apologize for the delayed response to this question. The October 3rd Game Manual update included revisions to the definitions of Possession and Plowing, as well as rule <SG7>, which we hope help to clarify your questions.

Plowing - A Robot / Triball status. A Robot is considered to be Plowing Triballs if the Robot is intentionally moving them in a preferred direction with a flat or convex face of the Robot.

Possession – A Robot / Triball status. A Robot is considered to be Possessing a Triball if a Robot’s change in direction would result in controlled movement of the Triball. This typically requires at least one of the following to be true:

  1. The Triball is fully supported by the Robot.

  2. The Robot is moving the Triball in a preferred direction with a concave face of the Robot (or inside of a concave angle formed by multiple mechanisms/faces of the Robot).

The difference between Possession and Plowing is analogous to the difference between the terms “controlling” and “moving”.

Examples A, B, C, and D - yes, these meet the intended definition of Possession.

Example E - Generally speaking, these mechanisms fall into three categories when interacting with Triballs.

(_______) - Definitely Possession

________ - Definitely Plowing

.______. - "Gray area" between Possession and Plowing

The third type of scenario requires some human / Head Referee judgment to determine which side of the line it falls on. For example, if it is a mechanism or face which is clearly designed to be flat, but incidentally bends inwards due to damage midway through a Match, then it is likely that only a warning or Minor Violation would be awarded. The incident only happened once, the Team has demonstrated intended compliance with the rule, and the Robot's behavior when interacting with Triballs is likely closer to Plowing than Possession.

If, on the other hand, the mechanism's "wings" had hard stops that only allowed them to open as far as is shown in your sketch, then it would be clear that there is no intention to comply with the stated definition of Plowing.

To provide another way to think about this difference... when reviewing a face, mechanism, or interaction, it is much easier to prove that "yes, this is Plowing", and much harder to prove that "no, it's not Possession". If it is flat or convex when placed against a wall, then you should be good to go - it is almost impossible to be considered Possession. If not, then you know that you're in a gray area, and that it risks a warning at minimum. And, as always, multiple warnings / Minor Violations may escalate to a Major Violation at the Head Referee's discretion.