[ymtc] c8


C8’s one of those bad rules that forces you to argue intent by calling it a “strategy”. If they took the ambiguity out of it and rewrote it to the effect of “force someone into a foul and it’s not a foul” then refs might be less afraid to call it.


If it was, that would be inaccurate. By the time 973’s bumpers were fully past the blue Cargo Ship line (when the ref started waiving the flag on red), their cargo intake was stowed in their starting configuration. There is a brief moment where it appears to move down a bit, but significantly after the foul is called.


d. pushing an opponent ROBOT against your ROCKET during the final twenty (20) seconds of the MATCH for the sole purpose of making them violate G16.

C8’s a tough call. By the wording of the fourth provided example for the rule, it seems to imply that the strategy must solely result in a point gain to result in an infraction. Thus, since the move by 5012 was just denying the scoring of points, it was legal?

If FIRST doesn’t make an explicit rule change defining how these situations are called, I expect that defensive strategies capitalizing on G9 will become the meta. It creates a huge threat area around the back cargo ship bays and side rocket bays for cycling robots, where they are most susceptible to being t-boned and pushed into the apposing zone.

Another example of this strategy can be found in Week 1 Southfield Semifinal Tiebreaker 2 (https://clips.twitch.tv/SingleBlitheLouseHotPokket)


C8 isnone of those rules that should be easy to implement.

In the case of this year’s game, it’s super simple. If an offensive robot is clearly scoring in their offensive zone and get pushed into the defensive zone while scoring, then there should be no penalty assessed.


The defensive robot accomplished its mission by preventing the team from scoring. If the expectation of the defensive team is that the offensive robot should get a penalty, then that, by definition, means it was strategic.

Again, no one did anything wrong in this incident so no penalty should be assessed. I saw it called correctly many times when an offensive robot pushed a defensive robot into the hab zone and contacted the defender when the entirety of the offensive robot was in the Hab zone (no call). It should also be called the same way in the case of the centerline.


C8 should have been called, but there is also priority when it comes to rules.

According to one of the CHS refs, rules like that will not always be prioritized because they are harder to implement, as “strategic” is subjective. G9 is extremely easy to implement, and will therefore be implemented more often.


I did ask this question on this forum a month ago to minimal response:

The problem I have is there is nothing in C8 that precludes C8 on C8.
This is the logical flow chart:

  1. G10 on robot A for being pushed across is outside frame perimeter.
  2. C8 on robot B because pushing caused robot A being in violation of G10.
  3. C8 on robot A because their being out of frame perimeter caused the C8 on robot B.
    It seems like a logical mess to me.

The easy way out for the referees is to start a G18 pin count. The blue box in G9 gives G18 priority over G9 and G10. That’s really what is happening anyways.


I questioned the same rule.

It should either be defense penalty or no penalty at all. 973 was not breaking a rule by will


The ruling on the field at Palmetto was that for that foul to be called, the robot had to voluntarily cross the line or voluntarily remain across the line after contact stopped.

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I agree completely Mike, I think that would be a no call. Hopefully this is clarified for Week 2.


This is something our driver plans to ask the Head Ref at our drivers’ meetings. I observed this happen multiple times during the playoffs of Del Mar, and each time it was called an ordinary foul (not C8) on the pushed alliance. If it’s called like that, it makes defense significantly weaker. To be clear there are two situations where this comes into to play: pushing a robot to your side of the field, and pushing a robot into the Hab zone. If I were a ref, the way I’d want to call it is a no call when a robot is pushed to violate the rule, plus a C8 call if it was repeated or obviously intentionally to cause a foul. I’d have to RTFM to confirm that this ruling would be allowed, though (and I think the wording should be changed if there is nothing between a C8 call and an ordinary foul call).

In short, I agree with Paul Copioli, but I’m unsure if the rules actually permit a ref to call it like that.

However, there is some gray area here. In the finals (match 1) of Del Mar, I saw some interactions were 399 was playing solid defense against 4414 who was attempting to score on the far side of the rocket. 4414 was being bumped a lot by 399, but it appeared to me that the robot was also briefly traveling to the opposite side of the field under its own power. What should be the call in this case? I think it’s reasonable to expect teams to be wary of scoring on the far side of the rocket if there is heavy defense.


The Q&A addressed a similar C8 question today: https://frc-qa.firstinspires.org/qa/393


This is kind of ancient history, but as I recall, in 2012, if a defensive robot got in the way of robots getting on the bridge, and was pushed into the bridge, the defensive robot would be considered to be at fault and penalized. Fairly certain the C8 rule existed back then.

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So, if you’re playing offense and get pushed to the defensive side while you have an alliance partner there you get a foul called against you, but if you’re playing defense and get pushed into the opposing HAB, you get a free ride to stay there the rest of the match?


Although I don’t doubt it’s the rule’s intent I think it’s being called correctly as written. “Strategies clearly aimed at forcing the opposing ALLIANCE to violate a rule” is the only reason C8 should ever be called. As a defensive bot my intent is to push the opposing offensive robot all the way to the other side of the field because it slows down their scoring. If that alliance already had a bot on my side of the field according to the rules that’s a G9. They are in charge of watching for this and their defense needs to get back before they violate G9.

Defense is inherently risky. Sending a robot to the other side of the field leaves you open to all sorts of penalties, so unless they change the wording on the rule I would only do it if you know the risks.

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Here’s another C8 question.

Blue robot drives, of it’s own accord, into the red half of the field to play defense. Blue has a mechanism outside their FP, cannot retract it, and starts incurring a G10 penalty every 5 seconds. Red notices what is happening, and parks near the midline to prevent the blue robot from crossing back.

At what point does this become a C8? Does it ever?


I think it’s C8 once blue runs into red and then red doesn’t let them by.


It depends a lot on the situation. If red blocks bot side routes, then it gets to be a pretty clear violation, but C8 isn’t the only rule available. If red only blocks the nearest one, then it might be, or it might not be.

Bear in mind: C8 requires that the victim team have little or no chance to avoid the fouls


From the way you described it that would be a violation of C8 but in real life I doubt that would happen. There are often nuances but if it was clear they were just trying to keep them on their side that would 100% be C8.


C8 should only be used when it is obviously malicious in intent, and not part if any other strategy. Such as pushing a disabled robot into the rocket during the last 20 seconds. That could be argued to be C8 as not only is it forcing them into a penalty, but there is no other reason to do it. In fact it is most likely detrimental to you as it bocks your path. Pushing a robot towards your side is a strategy. 4476 used it in Durham to stop climbs. I agree the rule needs to be changed as tipping over a little bit should not decide games, but in the end the defensive strategy is to get you away from scoring, and you cannot score if you are not on your side. We do not want FRC to become a game where certain strategies are punished. That limits the scope of teams and harms smaller teams. What needs to change is the rule on two robots. It needs to be like the hab rule, and only apply if the robot is fully over the opponents hab line.

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I don’t think it will be called which sucks for red.

How do you prove that red KNOWS blue is being penalized? They could be blocking just to hinder them in general.

You can’t just say “everybody knows that blue is being penalized for being outside their frame”. I just watched a driver this morning incur 30pts in penalties for playing defense with their arm obviously hanging out.

At champs I would expect more people to have a better grasp of the rules, but obviously not today.