Final YMTC of 07-08: Bluabot hits the E-stop in an awkward spot

Before I announce what appears to be my final YMTC of the 2007-2008 *FIRST *Robotics Competition season, I would like to personally and sincerely thank all those who were responsible for the creation of this year’s game: Overdrive. The game is exciting and fast-paced. Furthermore, the rules have been extremely well-written and have made it quite difficult to concoct contentious YMTCs. So thank you 2008 GDC! You Make The Call (YMTC) is a series of situations where you are the official and make the call.
Please reference specific rules when applicable. The results of YMTC are not official and are for educational purposes only.

*Welcome to the inaugural Dogwood Regional! Bluateam worked hard all season to design and build Bluabot: a hard-nosed, defensive tank of a robot. When fully functional, Bluabot has dominated Dogwood’s top-scoring hurdlers with impenetrable ball-prevention defense. Unfortunately, the tank treads that have made Bluabot “un-pushable” have, on occasion, come off; thereby rendering Bluabot truly immobile.

Early in their final match on Friday afternoon, Bluabot is playing strong ball-prevention defense on top-seeded Redabot in the area of the lane-marker near the Blue Alliance Station when Bluabot’s right tread comes off! Not wanting to damage the carpet or draw a penalty for driving on metal track rollers or for impeding Redabot, Bluateam immediately presses the E-stop button. They can only watch as Redabot now has the opportunity to play offense unopposed for the remainder of the match.

But wait! Redabot is in a position exactly as illustrated in Team Update #15! Redabot has just crossed the lane-marker, but with no room to maneuver past Bluabot without breaking the plane and violating Rule <G22>. Hearing over the loudspeaker that Bluateam has disabled Bluabot using the E-stop button, Redateam tries to use Redabot to push Bluabot out of the way. But after 8 seconds of all-out pushing, Bluabot still won’t budge! Knowing that victory in the match depends on Redabot hurdling at least a few more times, Redabot throws it into reverse, breaks the plane of the lane-marker, and then drives forward around the motionless Bluabot to take the offensive.

The remainder of the match is carried out penalty-free. After the buzzer sounds, the refs huddle to determine what, if any, penalties ought to be enforced. *

Based on the 2008 Rules, YOU MAKE THE CALL!

Team Update 15.pdf (135 KB)

Team Update 15.pdf (135 KB)

It’s still the responsiblity of the drivers of Redabot to avoid situations like the one described above, especially since Bluabot is considered field debris. I say penalty on Redabot.

<G36> specifically says that disabled robots cannot receive penalties for IMPEDING, so Bluabot does not receive a penalty. Update #15 clarified a particular situation where IMPEDING could occur, but does not under any circumstances give Redabot a free pass to violate <G22>, even if Bluabot was active and determined to be IMPEDING. -10 for Redabot.

<G23> No penalties.

Bluabot put Redabot into a situation where they had to take a penalty.

what Joe Gannon said, exactly.

Nice try. You can’t impede your alliance partner. (Not to mention, a disabled robot that is hurdling is quite a feat…)

No penalty, other than a standard <G22> violation.

(Now, if this were Redabot, probably none, or a <G22>.)

<G36> specifically says that robots that are disabled **after becoming incapacitated **will not receive further penalties. Bluabot in this situation cannot be ruled incapacitated unless they try and move out of the way. You cannot receive protection under G36 because you are scared of receiving a penalty which doesn’t exist. If they damage the field they will be disabled by the referee (no penalty). Until that decision is made or they have shown that they trully cannot move, then they must at least try and move out of the way.

I wan’t to change my answer.
-10 Blue
-10 Red

Similar result, different reason.

Derek, they’ve already disabled because they are incapacitated. They can’t drive, pretty much. If they do try, the refs will disable them (instead of disabling themselves). No impeding call (there was a passing lane), no field damage call. Just a <G22> on the other alliance.

Then again, as I said before, it’s a pretty good trick to have a robot that’s disabled hurdling.

My argument is that they aren’t incapacitated. As a referee you can’t make that determination until they try to move. I have seen many robots move around with one tread. Heck, we’ve done it in the past. It didn’t drive straight, but we would have been able to move out of the way.

As a referee, I couldn’t see myself calling a penalty on red because blue’s robot failed. With the rules as written, I can make a pretty good argument that there should be no penalty or one penalty each.

Ah, OK.

Now, how do you call a penalty on Red in the scenario AS WRITTEN?

I can’t, the scenario is written all wrong.

I can’t see anywhere in the rules where crossing the line is “forgiven”. If the trapped Redabot wants to avoid a G22 penalty, perhaps they need some help from an alliance partner to push the disabled Bluabot out of the way… or needed to design a machine with a bit more “push”…

G36 is pretty specific about this:

“ROBOTS that are disabled in this manner can not incur further PENALTIES (e.g. can not receive a PENALTY for IMPEDING). Disabled ROBOTS may be pushed out of the path of travel without PENALTY.”

This means that it is clearly the intent of the GDC that robots be able to push disabled robots out of their way.

And thanks for making the effort to find the YMTC scenarios, however, here’s an addendum to this one…

So what if one of Redabots’ alliance partners pushed Bluabot backwards, thus pushing Redabot backwards over the line? G23 comes into play… Does Bluabot still count as an “opposing robot”? Does being disabled and pushed count as an “action”? Bluabot can’t get any further penalties (and wouldn’t even if they were still active, as they are being pushed), but does Redabot get a G22 penalty in this case?


<G23> can cause a penalty to be “excused” if the opposing alliance causes he penalty to happen. I could argue that red wouldn’t have taken a penalty if blue hadn’t lost a tread and therefore blue caused red to take a penalty.

I prefer the other argument better. It’s more interesting.

The “in this manner” portion of this rule is referencing the line before that says the robot was disabled after being incapacitated. My argument is that the referee cannot know that they are truly incapacitated unless they at least make an attempt to move out of the way.

I think you may be misreading <G23>. Look at the examples again to understand what “cause an opposing ROBOT to break a rule” means. Pushing an opposing robot backwards over a line would not trigger a <G22> penalty, per <G23>. Stopping in front of an opposing robot, who then backs up over the line under their own power to go around, would be a violation of <G22>. That was something to learn from Update #15… you don’t get a free pass to break <G22> just because somebody stopped in front of you. In any case, you are certainly not forced to take a penalty, as you have the option to just sit still, or wait for Redabot2 to come help you push Bluabot out of the way. <G23> is about being forced into a penalty situation (such as being pushed backwards over a line, or having a trackball placed onto you), not about taking a penalty fully under your own power in order to get more points.

I think that this whole thing stinks for Redabot, but because there is no leeway in the rules, that’s how it would have to be called.

I appreciate the first argument, and contemplated it while formulating my initial response. I feel that Bluabot did not cause Redabot to cross the line, but rather placed it in a situation where it was forced with the choice of crossing the line or remaining immobile… or having an alliance partner assist in moving Bluabot. In no case, however, did Bluabot *cause *Redabot to incur a G22 penalty.

The second argument, I agree, bears perhaps a bit more weight in that the definition of “incapacitated” and who makes the determination of incapacitated is not specific. It does not, however, require a referee to make the decision that a robot is incapacitated. Rather it infers that the decision is up to the team by stating that the disablement must come through the pushing of the E-Stop in the player station. Secondly, when it states “robots that are disabled in this manner”, I believe there is room to argue that “in this manner” refers simply to the pushing of the E-Stop button.

I always figure it is a good YMTC when experienced FIRSTers can interpret the same situation in different ways. I see your points and would… if I were in Redabot’s shoes, put forward the same ones.


I believe that lword was put in there to specifically prevent a team or alliance from blocking the field and pressing the E-Stop. Otherwise, why would it be there.

Just because it’s not in the example doesn’t mean blueabot can’t be considered as causing the penalties.

Heck, if we go on that theory, then my other argument bears even more weight. I don’t see losing a tread in the examples of what makes a robot incapacitated.

I agree that the cause and effect here is a lot less clear than a robot pushing another backwards. The way I look at it is this. If blueabot didn’t break then redabot wouldn’t have taken a penalty, therefore, I can argue that bluabot caused the penalty.

If I were in Blueabots shoes I would call my arguments weak. But these threads or no fun if everyone agrees.

Guys, maybe i am misreading, but this looks pretty cut and dry…

Bluabot has been e-stopped and is now barred from receiving penalties. Redabot is in the exact situation described in update #15 which states:
“When a robot gets stuck between a Finish Line or Lane Marker and an opponent
Robot, because they would have to incur a <G22> penalty by backing across the
line in order to gain access to a free passing lane (see figure), that Robot is to be
considered to be IMPEDED and not to have a free passing lane. Therefore <G40>
and <G41> apply and a six-second count will be started on the Robot causing it to
be stuck there. This will give the stuck Robot an opportunity to begin moving again
six seconds later without having to incur a penalty.”

Because Redabot pushed for 8 seconds (which would give them 2 seconds over the time period needed to wait as per update #15), they now have the opportunity to begin moving without incurring a penalty.

No penalty for redabot because they waited the 6 seconds, no penalty for bluabot because they hit the e stop.

Update #15 is worded a little funny, but my understanding is that the update didn’t change <G22>, it just added an additional example to <G40> and <G41>. I wouldn’t swear to this, but I’m reasonably confident that “an opportunity to begin moving again six seconds later” refers to the other robot moving out of the way to avoid the <G41> penalty. In any case, there is no leeway in <G22> that would allow what you suggest.

How loose of a chain of actions would you permit to be considered causal? If Redabot took possession of Bluabot’s trackball, I don’t think you’d excuse the penalty on the grounds that it wouldn’t have happened if Bluabot hadn’t knocked the ball down in the first place. How about when Redabot gets tangled up in the overpass by Bluabot, and Redabot2 backs up over the line to free them? The only way this rule makes sense is if somebody else forced you to violate a rule when you didn’t want to. Redabot’s hand is not forced here; they have other options.

(It is worth noting that something very similar to the original scenario happened in finals match 2 at Buckeye, with the added trickiness that Redabot’s gripper ended up stuck pretty deeply into Bluabot, and continuing to try to push them could cause serious damage to Bluabot. After at least six seconds, Redabot backed out, and the head ref flagged them for a game-deciding <G22>. Perhaps that isn’t the right call, but at least it’s some indication of how this rule is being interpreted elsewhere.)

In this situation the only thing i see about it is consider both bots just 28"by38" boxes, place on sideways and the other one inbetween the sideways one and the finish line. Does the “trapped” bot have a way to go? yes sideways, it’d just require your bot to be able to drive sideways

I cannot see that update #15 is written to make a team sit there for 6 seconds, only to determine if another robot will move or not. I think it is very clear that the rule is there to allow a team to break <G22> by “bumping to pass” waiting the full 6 seconds, and then proceeding without incurring a penalty…i believe that is the instance. <G22> doesn’t change…however “proceed without incurring a penalty” seems to me that it is made to allow an instance for a team to go around a robot that is impeding them. In this case the bluabot is impeding, however because of the e-stop they do not incur that penalty.