Two Boulder Auto

[MrForbes]

Originally Posted by AlexanderTheOK

Considering the size of the balls, your margin of error would be several inches. Considering the fact that FRC teams dont have access to any global localization on the field, I can't see any modern sensors allowing that level of precision.

the auto line is pretty close to the midline, if you can detect it with an optical sensor, and slowly advance the robot the necessary amount, you could get right where you need to be.

[Lil' Lavery]

Originally Posted by AlexanderTheOK

Considering the size of the balls, your margin of error would be several inches. Considering the fact that FRC teams dont have access to any global localization on the field, I can't see any modern sensors allowing that level of precision.

Disagree entirely. There are teams that have achieved greater levels of precision control in the past, and achieved similarly difficult challenges. Namely, there were a handful of teams capable of retrieving and scoring balls from the side bridges during autonomous in 2012. If mechanical designs permit going underneath the low bar, that's a pretty similar challenge to spy bots scoring a second boulder in autonomous.

[AlexanderTheOK]

Originally Posted by Lil' Lavery

Disagree entirely. There are teams that have achieved greater levels of precision control in the past, and achieved similarly difficult challenges. Namely, there were a handful of teams capable of retrieving and scoring balls from the side bridges during autonomous in 2012. If mechanical designs permit going underneath the low bar, that's a pretty similar challenge to spy bots scoring a second boulder in autonomous.

This comparison isn't particularly valid. retrieving balls from the bridges requires only that you be able to reach the bridge and push it down. Depending on your mechanism your margin of error could be as great as three feet.

Maybe youre missing the fact that crossing the midline is a FOUL, and the ball is exactly on the midline. You see the issue? Your margin of error is now literally the radius of the ball.

[Lil' Lavery]

Originally Posted by AlexanderTheOK

This comparison isn't particularly valid. retrieving balls from the bridges requires only that you be able to reach the bridge and push it down. Depending on your mechanism your margin of error could be as great as three feet.

Maybe youre missing the fact that crossing the midline is a FOUL, and the ball is exactly on the midline. You see the issue? Your margin of error is now literally the radius of the ball.

I'm not missing either of those. Teams at every event each year run autonomous modes with margins of error less than the radius of the game ball this year. The same penalties existed in 2013, and there were teams that retrieved frisbees from the center line.

[mrnoble]

Two ball auto will happen, from at least one team at every event after week three. Three ball auto from a spy bot will happen at least once this season.

[Aren Siekmeier]

Originally Posted by Lil' Lavery

I'm not missing either of those. Teams at every event each year run autonomous modes with margins of error less than the radius of the game ball this year. The same penalties existed in 2013, and there were teams that retrieved frisbees from the center line.

There was no penalty in 2013 for partially crossing the midline, only completely crossing it. Even the penalties for opposing robot contact were contingent on being completely over the line. Center line auto modes would fight over those discs in the middle, or simply park over them.

Originally Posted by 2013 Game Manual

G19
During AUTO, a ROBOT may not cross the CENTER LINE such that it is no longer in contact with the carpet on its
starting half of the FIELD.
Violation: FOUL. If contact with an opponent ROBOT, TECHNICAL FOUL.

I completely agree with you concerning sensor precision, however. This is within the means of FRC teams. The challenge is the 15 second time limit as much as it is precise navigation.

[Nyxyxylyth]

Originally Posted by christheman200

You could also have one bot kick all the mid-line balls over to the low bar for another bot to fire. If any two teams can pull this off they'd ensure a win.

That violates G38 and G40, unless the midline bot waits until the low bar bot shoots before it kicks the next ball, and unless the low bar bot then crosses into the courtyard and comes back before receiving the next ball.

[AlexanderTheOK]

Originally Posted by Lil' Lavery

I'm not missing either of those. Teams at every event each year run autonomous modes with margins of error less than the radius of the game ball this year. The same penalties existed in 2013, and there were teams that retrieved frisbees from the center line.

It doesn't seem like you remember EITHER of those games. In 2013 you weren't allowed to COMPLETELY cross the line. This means your margin of error is the width of your robot, or most likely the width of your intake, again, several feet.

I've never seen a robot that consistently moved to within +-2 inches in the long axis. If you have an example please share.

[Lil' Lavery]

Originally Posted by AlexanderTheOK

It doesn't seem like you remember EITHER of those games. In 2013 you weren't allowed to COMPLETELY cross the line. This means your margin of error is the width of your robot, or most likely the width of your intake, again, several feet.

I've never seen a robot that consistently moved to within +-2 inches in the long axis. If you have an example please share.

I remember both of those games plenty well. Please watch your tone.

The exact specifics of the rules in 2013 vs 2016 differ (obviously), but the intent is largely the same. The margin for error for many teams was rather small, especially when it came to aligning their intake devices. The specific example I had in mind:
https://www.youtube.com/watch?v=2j9ov03mOyA (987)
https://www.youtube.com/watch?v=y9fHnHGvM8s (987, gets hit, corrects, still makes shots)

[Mulcahy]

Good times....

[AlexanderTheOK]

Originally Posted by Lil' Lavery

I remember both of those games plenty well. Please watch your tone.

The exact specifics of the rules in 2013 vs 2016 differ (obviously), but the intent is largely the same. The margin for error for many teams was rather small, especially when it came to aligning their intake devices. The specific example I had in mind:
https://www.youtube.com/watch?v=2j9ov03mOyA (987)
https://www.youtube.com/watch?v=y9fHnHGvM8s (987, gets hit, corrects, still makes shots)

I apologize that you found offense in my statement, however, I hope you understand that giving two factually incorrect statements in a row gives off a particularly negative impression on one's memory, so I wouldn't say my statement was particularly out of line.

I will reiterate my point once again:

In 2013, the margin of error would be defined by the construction and design of your intake, and the teams that were good enough to go for the mid-line Frisbees also had intakes that would successfully capture Frisbees over their entirety. This left such teams with enough clearance that localization via encoders and IMU would yield error that would not affect intake effectiveness.

In addition, the margin of error for getting a foul was that of your entire robot, which would be several feet, meaning if a team WAS to miss the frisbees, they would not accrue a foul. In 2016, crossing the midline in any way is a foul.

While I would hope Q&A would change this rule to lower the potential risk of going after a second boulder, the rules as they are give a margin of error that is nearly an order of magnitude lower than that of previous years.

Originally Posted by MrForbes

the auto line is pretty close to the midline, if you can detect it with an optical sensor, and slowly advance the robot the necessary amount, you could get right where you need to be.

Good point, this would give a team a point to relocalize. While I still don't see teams risking a foul for an extra 10 points, I could see teams getting their robot to do this so that it would work often enough to demonstrate.

[rich2202]

Originally Posted by AlexanderTheOK

I've never seen a robot that consistently moved to within +-2 inches in the long axis. If you have an example please share.

It is not hard to drive the alley between the mid-line and outerworks (more than +/- 2" leaway. Using vision, you can then accurately line up with the ball and approach it perpendicular to the mid-line. That is your best chance to be able to get the ball without crossing the mid-line.

[hardcopi]

I don't think the accuracy will be the downfall. Accuracy isn't beyond any of our teams. ie: https://www.youtube.com/watch?v=N995FopDHgU

I do wonder how many fouls will be racked up before the 2 boulder auto will be dialed in. Not sure it is going to be worth the potential fouls or not.

[sciencenuetzel]

A question for everyone and maybe it's already understood from previous years. (Year 2 for me)

Is the robots dimensions defined by the frame perimeter? (Meaning in light of this thread if my intake mechanism is 14 in outside of my perimeter is that part considered my ROBOT? Could the mechanism extend over the midline to grab the second ball in a two ball auto? If so would that be considered a violation of the rule as long as my frame perimeter did not cross the midline?

[sciencenuetzel]

Another question. Wouldn't it be worth it to get the 2nd ball in auto even if it was a foul?

If you hit both shots that is 10 points per ball. The foul costs you 5. But you gain the extra time by knocking down tower strength another notch....

Just thinking