[YMTC]: Breaking robots

Imagine a match in which Blue 1 is driving toward a live blue ball with its retractable intake extended beyond its frame perimeter, intending to possess the ball. Red 1 drives toward Blue 1, intending to prevent Blue 1 from picking the ball up.

Red 1 and Blue 1 collide, with Blue 1’s intake making contact inside Red 1’s frame perimeter. Neither team is using a strategy geared towards intentionally damaging the other team’s robot. However, part of Red 1 is broken as a result of the collision. The broken piece of the robot sticks out more than 20 in beyond the frame perimeter, and remains attached, but continuously sticking out for the remainder of the match.

What, if any, penalties should be assessed? You make the call.

Other things to consider:

  1. In this hypothetical scenario, we have the benefit of knowing the teams’ states of mind. Since the referees can only infer intent, should this uncertainty affect their ultimate decisions?
  2. Could the rulings be different in teleoperated mode vs. autonomous mode?
  3. What if the broken piece oscillated between legal and illegal positions?
  4. What if the broken piece were detached? (Intentionally or unintentionally, and by whom?)

1)We cannot comment absolutely on hypothetical situations, as there are factors that come into play outside this forum. But Red is driving for contact with Blue & Blue is driving for the Blue so it would be generally Reds penalty. if any. Extension beyond 20" penalty would depend on who was judged to have caused the damage.

  1. would depend on which side of the truss it occurred on of if red was in its goalie zone.

3)Might be better if blue went in the corner and his.

4)Pretty much covered by the rules.

As in all rules, the head referee would have the final decision for these kind of issues. Or any rules questions for that matter.

I am very curious to see how others would make the call on this one.

I suppose I will share my preliminary thoughts, which would be:

  1. Red 1 should be assessed a 50pt Tech Foul for extending continuously beyond 20".

  2. Blue 1 should be assessed a 20pt Foul for causing damage inside the frame perimeter to Red 1. It should NOT be a 50pt Tech Foul because it was not a strategic attempt to cause damage.

The net penalty advantage is +30pts for Blue.

It’s a rough scenario for both teams, as they each have a reason to be upset:

*Red 1 gets a Tech Foul even though it was their robot that was broken due to the collision.

Blue 1 gets a Foul even though all they did was try and pick up their own ball.
One could argue that a broken part sticking out of Red 1 beyond 20" creates a potential safety hazard to the many people standing at the edge of the field, thus “justifying” the 30pt net penalty. After the collision, Blue 1 never becomes a potential safety hazard, but Red 1 does. Although it seems like a large penalty hit, in relation to G40 - another safety-related rule that results in a 50pt swing, the net 30pt at least seems consistent.

As for the other considerations:

  1. Intent matters in this case. Blue 1’s intentions are the difference between Blue 1 getting a 20pt Foul vs a 50pt Tech Foul. In this case, the evidence for intentional strategic damage would probably have to be pretty compelling: Blue 1 no longer makes any attempt to pick up their ball at all, in fact their ball is nowhere nearby, and they drive full speed directly at Red 1 unimpeded with their intake out. That’s one of the only scenarios I can think of where the 50pt Tech Foul could be convincingly called over the 20pt Foul.

  2. Autonomous mode scenario. Assuming all other factors are the same, I wouldn’t change my assessment above. Even intentional strategic damage in autonomous per above is feasible if an obvious “torpedo” program is run where Blue 1 rams Red 1 with its intake out.

  3. Repeated >20" oscillations. If the broken part oscillates in and out of the 20" limit, I would consider this “repeatedly” which results in the same penalty as “continuous” - a single 50pt Tech Foul on Red 1. How many times would it have to oscillateto be considered repeated? Maybe 3?

  4. >20" part breaks off. This is where things get murky. If the broken part detaches completely from the robot, BEFORE it extends past 20" from the frame perimeter, it looks like there should be no penalty. If for a moment the part is still attached to the robot as it breaks the 20" limit, it is at least a 20pt Foul. Depending on how long the >20" broken part stays attached to the robot before it breaks completely off (is it continuous?), and if the broken part oscillates in and out of the 20" limit (is it repeated?) will dictate whether this is upgraded to a 50pt Tech Foul. Anecdotally, if I had made the call, staying extended for longer than about 5 seconds, or oscillating in and out of the 20" limit say, 3 times, would probably be my benchmarks.

As the rules are currently written, my interpretation and reasoning are as follows.

  1. Red 1 should be assessed a 50pt Tech Foul for extending continuously beyond 20" via G24. If the broken extension posed a safety hazard, they should be disabled, and receive an additional 20 pt foul via G3.

One could argue that Blue shouldn’t be able to force Red to take a foul by G14, but since Blue wasn’t engaging in a strategic attempt to force red to take the foul, it does not apply.

  1. Blue 1 should be assessed a 50pt Tech Foul for causing damage inside the frame perimeter to Red 1 regardless of intent via G28.

One could argue that a single 20pt foul via G27 should be called or a 20pt G27 and a 50pt G28, but G27 covers aggressive or repeated violent actions. As blue was attempting to grab a ball, and wasn’t actively engaging in any of the actions described in G27, I don’t feel it applies.

There is much room for interpretation in this years rules, and if I could throw out the rule book, and make a gut call, I’d say no foul for either team. Common sense dictates that there should be no possible interpretation where intentionally or unintentionally causing damage to your opponent can gain you an advantage, but as Mr. Lim points out, that is also one logical interpretation. The problem is that there seem to be so many logical interpretations, who knows what’s correct. The only thing I know for sure is, if I was a ref, I’d be calling FIRST HQ for clarification… if a hypothetical situation like this ever were to happen.

Based on the current rules, Red are violating G24 and should be penalized. Personally, I would prefer if G24 was re-written to eliminate inconsequential violations from robot damage, or violations caused by damage from another team.

Assuming Blue had their intake towards the ball, I would rule that G28 was not violated as Red caused the action (catalyst) for driving in to the ball/intake.

My interpretation of G27 was that the list of actions were descriptive of the sort of all penalty-inducing actions to a large enough degree (ie it has be one of the actions on the list or very similar to one). I also think G27 and G28 are meant to avoid overlapping/compounding each other. Therefore, I would be hesitant to describe the action in the hypothetical scenario as entanglement or any of the other actions. I would not penalize Blue for G27.

In summary, Blue would not be penalized and Red (regrettably) would be penalized 50 points.

I’ve been thinking about this one. Here’s another hypothetical:

Imagine Blue had been preparing to shoot on goal, rather than attempting to pick up their ball, while being defended by Red. Blue fires their shooter (which extends beyond the frame perimeter in this example), causing the same damage to Red described originally.

My intuition is that most people would give Blue the penalty in this scenario because they fired their catapult (that’s certainly how I see robots behaving on the field). However as far as I can read, this should incur the same penalties as the original scenario, under which several people have argued for Red’s penalty. The intentions and outcomes are the same - Blue was trying to accomplish normal play, Red was defending in a manner which could and did incur damage.

If my intuition is correct, then there is something that separates “shooting” from “intaking” that needs to be articulated. If I’m wrong, then teams should be playing a lot less carefully with their shooters on offence.


There is still the clause at the end of the G28 blue box that says “unless the actions of the damaged ROBOT are the catalyst for the damage.” Red 1 certainly catalysed that damage. They were playing defense on Blue 1.

I’m not sure I follow this line of reasoning. If you read “catalyze” too broadly, then every robot with an outstretched appendage gets a right of way - any defender / offender that gets hit by the appendage on the way risks being called a “catalyst” to their own damage.

Personally, I would set the “fault” line at “inside/outside” the frame perimeter. It seems more in keeping with the original bumper rules, and the blue box in G27: “Teams are encouraged to be cautious in their use of such appendages when engaging in ROBOT to ROBOT MATCH play”. Think of appendages as weapons - you have an extra burden of care when you deploy one.

That, of course, runs the risk of teams performing “suicide attacks” against appendages to try to draw damage, but I think that’s much less likely (and easier to spot).

The ‘catalyst’ clause was added as a team update, precisely because teams playing offense were penalized when defenders rammed in to their intake.

Blue are actively engaging their mechanism by picking up the ball, that’s why they are not considered the catalyst for the contact inside the frame perimeter.

Red are driving towards the ball or robot to make contact with ball/robot (ie play defense), so they are considered the catalyst.

G28 is “Deliberate” or “Damaging”. With Blue extended, they are taking the risk. If they cause unintentional damage, they still caused damage. G28 is a technical, and there is no lower “foul” for unintentional damage.

Which I think is good. The opponent could be negligently driving extended. If G28 required intent then how do you penalize them for negligence?

“Deliberate” without damage is hard to call. “Deliberate” would require repeated inside the frame contact with hope of causing damage. Again, “wanton disregard” is not “deliberate”. Thus, damage must be called, regardless of who initiated the contact. If you are the bull in the china shop, then you better be careful of the china.

Now, if the opponent drove at you with the intent to draw the G28 technical, then that would be a G14 violation, and G28 could be waived. They could also be in violation of G27 if they had the intention to damage the extended piece (playing the extension, and not the bot).

Am I alone in thinking this should be an absolute no-call?

No, you’re definitely not alone. Tyler Holtzman alluded to that in his analysis as well. I tend to agree with both of you also.

The real challenge I suppose is coming up with a set of rules that would allow a no-call (or offsetting ones) in situations like this, but still penalize more egregious situations.

I think of it from the perspective of the bot receiving the damage. Once they violate my frame perimeter, then all bets are off. They are taking the risk, and if they damage me, then the penalty is fully on them.

If you require robots to sustain contact within the frame perimeter without damage, that is imposing a much higher level of design (and weight).

If I design my bot to stay within the frame perimeter, then I am not at risk of causing damage to other robots. If I choose to extend outside the frame perimeter, then it is on me to make sure that I do not inadvertently damage other robots.