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The Q&A is closed for the 2021-2022 season. Any rule changes or clarifications pertaining to the 2022 VEX Robotics World Championship will be included in the April 5 Game Manual Update. Teams attending VEX Worlds who wish to pre-submit questions for the driver's meeting should have received a contact form via email; if not, please contact your REC Foundation Team Engagement Manager for more information.

Official Q&A: VRC 2021-2022: Tipping Point

Usage Guidelines All Questions

905: Trapping <G15>, <G3>, struggling over a neutral mobile goal


Barry Atwell (Event Partner)
1-Nov-2021

Trapping question:

Red allinace robot is in the corner holding 2 mobile goals. One goal is in front of the robot and one is in back of the robot so only one of the goals is over the corner tile in the red alliance home zone. The goal that is not in the corner is a neutral mobile goal. A blue alliance robot pushes into the robot in the process of trying to take away one of the mobile goals. The referee starts the 5 count for trapping. By the count of two, the blue alliance robot is moving toward the center of the field pulling the neutral mobile goal and by extension, the red alliance robot with it.

Both robots are now at the center of the field. Both robots have the opportunity to release the neutral mobile goal. Neither robot does release the mobile goal.

Rules and definitions to consider:

"Trapping – A Robot status. A Robot is Trapping if it has restricted an opposing Robot into a small, confined area of the field, approximately the size of one foam field tile or less, and has not provided an avenue for escape. Trapping can be direct (e.g. pinning an opponent to a field perimeter wall) or indirect (e.g. preventing a Robot from escaping from a corner of the field).

Note: If a Robot is not attempting to escape, then that Robot has not been Trapped." Page 8 Game manual v2.1

<G15> No Trapping for more than 5 seconds. A Robot may not Trap an opposing Robot for more than five seconds (0:05) during the Driver Controlled Period. A Trap is officially over once the Trapping Robot has moved away and the Robots are separated by at least two (2) feet (approximately one [1] foam tile). After ending a Trap, a Robot may not Trap the same Robot again for a duration of five seconds (0:05). If a Team does Trap the same Robot again, the count will resume from where it left off when the Trapping Robot initially backed off.

&lt;G3&gt; Use common sense. When reading and applying the various rules in this document, please remember that common sense always applies in the VEX Robotics Competition.

Q1: Is either robot obligated to release the mobile goal?

Q2: Is the obligation to move "away and the Robots are separated by at least two (2) feet" nulified by the trapped robot moving with the "trapping" robot when the robot moves away assuming the trapped robot has the ability to not move with the trapping robot? G3

Q3: Should the trapping count continue at the point that both robots are in the middle of the field and either robot can release the mobile goal and be separated. In other words, does the fact that the referee started the count obligate the Blue alliance robot to release the mobile goal in order to get 2 feet away or since both red and blue are mutually struggling for the robot and neither is forced to be there and there is certainly a path to "escape" should the count end once both robots are in the middle of the field with nothing restricting their movements other than struggling for the possession of the mobile goal?

Q4: Does it matter if the goal over which the teams are struggling is neutral?

Answered by committee

Please see the Note and "red box" from rule G12:

Note: Incidental damage that occurs due to interaction with a Robot in Possession of a Neutral Mobile Goal will, in most cases, not be considered a violation of <G12>. Intentional damage, tipping, or dangerous mechanisms may still be considered a violation of <R3>, <S1>, or <G1> at the Head Referee’s discretion.

VRC Tipping Point is intended to be an offensive, interactive game. Robots interacting with Neutral Mobile Goals should expect vigorous interactions from opponent Robots, especially if attempting to interact with multiple Mobile Goals at once.

On a similar note, please see rule G13, and most notably, its "red box".

<G13> Offensive Robots get the “benefit of the doubt”.

The following “rules of thumb” apply when determining offensive / defensive roles in the context of rule <G13>:

  • A Robot in Possession of its own Alliance Mobile Goal is generally playing an offensive role.
  • A Robot in Possession of an opponent’s Alliance Mobile Goal is generally playing a defensive role.
  • A Robot in Possession of a Neutral Mobile Goal is generally neither playing a defensive or offensive role. In the case of a destructive interaction between two Robots competing for the same Neutral Mobile Goal, the Note from <G12> will apply.

With that in mind, once the Blue Robot moves far enough away from the corner for the Red Robot to escape, this would no longer be considered a Trapping situation. The Red Robot's movement is no longer restricted, and they are no longer demonstrating an attempt to break free.

Since the Mobile Goal in question is a Neutral Mobile Goal, both robots are equally entitled to it, meaning that offensive / defensive roles do not apply. That is to say, once the Robots move away from the corner, this should be handled the same as if there was no Mobile Goal involved, and the two Robots are just driving into each other.

Q1: Is either robot obligated to release the mobile goal?

No.

Q2: Is the obligation to move "away and the Robots are separated by at least two (2) feet" nulified by the trapped robot moving with the "trapping" robot when the robot moves away assuming the trapped robot has the ability to not move with the trapping robot? G3

Yes. Again, this could be interpreted the same way as if there was no Mobile Goal involved. If a Trapping Robot backs away, and the Robot which was formerly being Trapped follows them, then the Trap situation ends because the formerly Trapped Robot is no longer demonstrating an attempt to break free.

Q3: Should the trapping count continue at the point that both robots are in the middle of the field and either robot can release the mobile goal and be separated. In other words, does the fact that the referee started the count obligate the Blue alliance robot to release the mobile goal in order to get 2 feet away or since both red and blue are mutually struggling for the robot and neither is forced to be there and there is certainly a path to "escape" should the count end once both robots are in the middle of the field with nothing restricting their movements other than struggling for the possession of the mobile goal?

The italicized portion of your quote is correct.

Q4: Does it matter if the goal over which the teams are struggling is neutral?

Sort of. If the Goal in question was a Red Alliance Mobile Goal, the Blue Robot would be definitively playing a defensive role. So, it could be subject to <G12> violations, if damage or tipping were to occur to the Red Robot.

However, with that being said, most of the answers regarding Trapping are still the same. By continuing to hold on to the Red Alliance Mobile Goal, the Red Robot is not demonstrating an attempt to escape. Again, it could be interpreted similarly to how this interaction would be handled if the Mobile Goal were not present.