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Official Q&A: VRC 2020-2021: Change Up

Usage Guidelines All Questions

Clarification on Q&A <G16> Answer (Reacting Against Multiple Sides of The Center Goal).


80X
1 year ago

A question about "Reacting Against Multiple Sides of The Center Goal" was answered here in the Q&A: www.robotevents.com/VRC/2020-2021/QA/603. The answer was along the lines of imagine pulling the mechanism in a random direction, to comply it should not "get stuck" or risk damaging anything. We are worried this could interfere with the more intended game play and have some further questions regarding this matter.

Figure 1 shows a hypothetical robot with intakes around a goal. It interacts with multiple sides of the goal in order to descore balls. "pulled in random directions" is a bit of a vague term; does it mean there needs to be at least one direction for the robot to be pulled and not "get stuck" or damage anything? If not how should a ref apply that to this case?.. since there is only one direction where not "get stuck" or damage anything can apply... Does this scenario comply with &lt;G16>? img

Additionally, what about a mechanism that releases when pulled a substantial enough force, but small enough to definitely not damage the field elements? Figure 2 shows an example of such a mechanism; the mechanism has "doors" which are closed using rubber bands, meaning if pulled with enough force, open. If such a mechanism required definitively less force to open then would damage a goal, would it be legal to put it around the center goal? img

Finally, "pulled in random directions", from the linked Q&A answer it seems that directly up (lifting it) doesn't seem to be an option when doing this check, is that correct? If a mechanism can only be lifted up off a goal does it pass or fail the test to comply with &lt;G16>?

Sorry for asking some slightly redundant seeming questions, we are just trying to be as thorough as possible.

Thank you from Vexmen Team 81K Magik

Answered by Game Design Committee

For reference, G16 reads as follows:

G16: Robots may not intentionally grasp, grapple or attach to any Field Elements. Strategies with mechanisms that react against multiple sides of a Field Element in an effort to latch or clamp onto said Field Element are prohibited. The intent of this rule is to prevent Teams from both unintentionally damaging the field and/or from anchoring themselves to the field.

Minor violations of this rule that do not affect the Match will result in a warning. Match Affecting offenses will result in a Disqualification. Teams that receive multiple warnings may also receive a Disqualification at the Head Referee’s discretion.

The relevant portion of the linked Q&A post is as follows:

As noted in the quoted portion, one intent of G16 is to prevent teams from "anchoring" themselves to the field. The primary thought experiment that Head Referees should use to determine whether a Robot has "anchored" itself to a field element is to envision the Robot being pulled in any random direction by a strong force (such as a human or an opposing Robot).

When it is pulled in random directions, does the Robot "get stuck" on the field element? Does it run a risk of damaging the field? Does it run the risk of damaging itself (a la G5)?

It may be more straightforward, albeit more verbose, to phrase as the following:

To test whether a Robot is violating G16, the Robot should be able to be pulled away from the Goal in some horizontal direction, without lifting the Robot off of the field tiles, and without damaging, disassembling, or violating any laws of physics of the Goal and/or Robot.

By this revised thought experiment, the two examples depicted would likely not be in violation of G16.

However, this judgment call is highly dependent on the specifics of the mechanism in question, how it interacts with the Goal, and any prior warnings/DQ's received by the Team. As always, it is impossible to provide a blanket answer that will definitively encompass all hypothetical mechanism designs and interactions. If a Team is concerned that a mechanism may dance on the edge of a potential G16 violation, we would advise them to design their Robot in such a way that it is abundantly clear to Head Referees that the Robot is not anchored, grappled, latched, clamped, or otherwise attached to the Goal.