Battle of the Middle Bridge

[LH Machinist]

I’m seeing a few designs that imply tilting the center bridge in hybrid and I expect we’ll see a few instances when robots from both alliances attempt this. The big question is - who will win/survive the ensuing teeter-totter battle.

[Taylor]

I’m seeing a few designs that imply tilting the center bridge in hybrid and I expect we’ll see a few instances when robots from both alliances attempt this. The big question is - who will win/survive the ensuing teeter-totter battle.

The one that gets there first.

[Andrew Lawrence]

That, or the one with the most torque applied at the best angle.

However, like Taylor said, the one that gets there first will win, all the time.

[Jared Russell]

The one that gets there first.

There's something to be said for the one who pushes harder, too :)

[Taylor]

There's something to be said for the one who pushes harder, too :)

By that time, the bridge is pushed up out of reach.

[Jared Russell]

By that time, the bridge is pushed up out of reach.

Depends on your reach.

[Andrew Lawrence]

Depends on your reach.

Whatever it is it won't be past 14".

[MrForbes]

That's one reason I'm glad we didn't get around to programming that feature in our autonomous code....another is that last year we kind of tore up our robot by having it drive too far in auto most matches.

[Wayne TenBrink]

The challenge is getting there asap without driving full speed into a raised bridge...

[LH Machinist]

Agreed, first in wins - what if it's a tie? It becomes a force game and that is when it becomes intresting...broken arms, 2 foot drops or a flip are all possible.

[Andrew Lawrence]

The challenge is getting there asap without driving full speed into a raised bridge...

So that brings up a good question: Which is more important? Scoring the balls you have in hybrid, or getting the balls off the bridges onto your side.

To quote my favorite announcer: Let's do the math:

In hybrid mode, each robot starts off with two balls, and there are two balls on each bridge, assuming all 6 robots use both of their allotted balls.

The score in hybrid mode is (normal_score + 3), so each ball is potentially worth 6 points. That's 36 points if all 3 robots score both of their balls in the top hoop during hybrid, which will require some coordination, meaning there will be a first robot, a middle one, and a last one, most likely shooting in the end of hybrid.

If you use hybrid mode to get all balls off the bridges and onto your side (one bridge per each robot on the alliance), than you will have 12 balls on your side, a little more than each robot can handle. If all 12 of those make it to the top basket, it's worth 36 points.

So in the scenario of going for the bridge vs. going for the points, both will give you 36 points.

Now let's mix it up a little. Say you have all 3 robots taking turns shooting in hybrid, but the first robot goes for a bridge once it's done. That's the 36 points of hybrid from all 6 balls, and +6 points for the two balls that were on the bridge, assuming they were scored in teleop, giving an almost instant score of 42 points.

New scenario: The same thing is done, but with the 2nd robot also going to a bridge. By this time, the first robot probably got the balls off of its bridge down, and the 3rd robot is getting ready to shoot. There are only two bridges left, and chances are your opponents will be going for a bridge as well. IF your second robot gets the balls onto your side, that's another +6 points for your alliance, getting you to a score of 48 points, 12 points above your opponents.

In conclusion, the balls on the bridge will only improve your score if you can gather them AND have all 6 robots on your alliance score in hybrid mode.

Just something to think about when doing autonomous strategies.

[Swampdude]

Here's one of ours (http://www.youtube.com/watch?v=wD3R8JyZycw) It's not an easy thing to do quickly without risk of careening off balls and missing your mark etc. A bot that could to this while shooting/making baskets would be quite an asset.

[pyroslev]

The team with the Kinect that can do it in conjunction with the arm with the most apropos application of torque and an arm that can has options.

[LH Machinist]

So that brings up a good question: Which is more important? Scoring the balls you have in hybrid, or getting the balls off the bridges onto your side.

To quote my favorite announcer: Let's do the math:

In hybrid mode, each robot starts off with two balls, and there are two balls on each bridge, assuming all 6 robots use both of their allotted balls.

The score in hybrid mode is (normal_score + 3), so each ball is potentially worth 6 points. That's 36 points if all 3 robots score both of their balls in the top hoop during hybrid, which will require some coordination, meaning there will be a first robot, a middle one, and a last one, most likely shooting in the end of hybrid.

If you use hybrid mode to get all balls off the bridges and onto your side (one bridge per each robot on the alliance), than you will have 12 balls on your side, a little more than each robot can handle. If all 12 of those make it to the top basket, it's worth 36 points.

So in the scenario of going for the bridge vs. going for the points, both will give you 36 points.

Now let's mix it up a little. Say you have all 3 robots taking turns shooting in hybrid, but the first robot goes for a bridge once it's done. That's the 36 points of hybrid from all 6 balls, and +6 points for the two balls that were on the bridge, assuming they were scored in teleop, giving an almost instant score of 42 points.

New scenario: The same thing is done, but with the 2nd robot also going to a bridge. By this time, the first robot probably got the balls off of its bridge down, and the 3rd robot is getting ready to shoot. There are only two bridges left, and chances are your opponents will be going for a bridge as well. IF your second robot gets the balls onto your side, that's another +6 points for your alliance, getting you to a score of 48 points, 12 points above your opponents.

In conclusion, the balls on the bridge will only improve your score if you can gather them AND have all 6 robots on your alliance score in hybrid mode.

Just something to think about when doing autonomous strategies.

An aggressive strategy would be - shoot both of your allocated ball and then go for the middle bridge. The remaining bridge balls are off limits to the opposing alliance.

[Andrew Lawrence]

The team with the Kinect that can do it in conjunction with the arm with the most apropos application of torque and an arm that can has options.

Agreed. The team using the kinect will have the most control over their robot during hybrid, so they will most likely be the ones getting the bridge down the fastest. And the implementation of commands to change the robot speed at will will be pretty helpful. ;)

[Andrew Lawrence]

An aggressive strategy would be - shoot both of your allocated ball and then go for the middle bridge. The remaining bridge balls are off limits to the opposing alliance.

Wait, really? You can't even get the balls from your own bridge?

[engunneer]

Here is FRC23 winning a battle. Reportedly, the opposing robot was using pneumatics to push.
http://www.youtube.com/watch?v=7d9JgsXzhk0

[jwfoss]

Here is FRC23 winning a battle. Reportedly, the opposing robot was using pneumatics to push.
http://www.youtube.com/watch?v=7d9JgsXzhk0

They beat us to the bridge but not by much. Once our drivers realized they weren't going to beat the cannon of 23 with our pnuematic bridge manipulator, they gave up to not waste any more time. If you look at other videos from the Suffield Shakedown there are matches where a pneumatic appendage beats a motor driven appendage. Its going to depend on every teams design.

I'd say that the center bridge during or right after hybrid will be fought over it nearly every match this season.

[engunneer]

Good job on your drivers to give up once the balls were going the other way. An important skill in driving is to know when to alter your strategy. I think 23 got there a hair before you, and had the advantage (that time). I think it will come down to whoever is first, followed by whoever is strongest. One wrong twitch and the cannon might have fallen off the bridge.

Robots who consistently win bridge balls during auto/hybrid will make good partners. I think this discussion also shows that there should never be a reason to not have all your available balls in the robot at the start. A ball balanced on top of your robot that falls to your side of the field is better than a ball lost to the opponent's side if they win a bridge battle.

Bridge battles now need a name. Tip-o-war? (from tug-o-war)

[V_Chip]

Good job on your drivers to give up once the balls were going the other way. An important skill in driving is to know when to alter your strategy. I think 23 got there a hair before you, and had the advantage (that time). I think it will come down to whoever is first, followed by whoever is strongest. One wrong twitch and the cannon might have fallen off the bridge.

Robots who consistently win bridge balls during auto/hybrid will make good partners. I think this discussion also shows that there should never be a reason to not have all your available balls in the robot at the start. A ball balanced on top of your robot that falls to your side of the field is better than a ball lost to the opponent's side if they win a bridge battle.

Bridge battles now need a name. Tip-o-war? (from tug-o-war)

QFT.

At Suffield Scrimmage 2168 and 175 were constantly battling for the center bridge. Though we made it there quicker, our device was more difficult to align and lacked necessary torque.

[Eric Kosek]

Or shoot your balls while you are drivng toward the bridge......

[GaryVoshol]

If you use hybrid mode to get all balls off the bridges and onto your side (one bridge per each robot on the alliance), than you will have 12 balls on your side, a little more than each robot can handle. If all 12 of those make it to the top basket, it's worth 36 points.
But you've given your opponents 9 points for the [G25] technical foul.

[engunneer]

But you've given your opponents 9 points for the [G25] technical foul.

QFT.

Make sure your drivers know the rules. This is also why the balls on your color are safe. If your opponent gets them, you get 9 points free. All you have to win is the middle.

Granted, getting the two from your bridge to your side during auto (without accidentally tipping it the other way!) is still helpful

[pyroslev]

Or shoot your balls while you are drivng toward the bridge......

With a flexible arm just in case you don't have a lovely turret.

[Andrew Lawrence]

But you've given your opponents 9 points for the [G25] technical foul.

I forgot the opponent's bridge was off-limits. :o Thanks for the clarification.

[Bill_B]

...
In conclusion, the balls on the bridge will only improve your score if you can gather them AND have all 6 robots on your alliance score in hybrid mode.

Just something to think about when doing autonomous strategies.
I was trying to do the math ;) - - when I found that this should read
have all 6 balls on your alliance robots score in hybrid mode.

or
have all 3 robots on your alliance score their allocated balls in hybrid mode.

You've already reduced the number of extras to the likely number of 4, I think.

[JesseK]

Actually getting the 2 balls from the opponent's bridge every time still nets a 3-point gain if they're both put into the high goal in autonomous. Of course, if 1 ball misses...

We're using flexible passive actuation to pull the bridges down and active actuation to bring the device back into the bot. That way if we lose the battle of the bridge, we don't break anything on the bot. I'll have a reveal collage later this week.

If an alliance doesn't have an autonomous planned for the middle bridge, then that's a mistake -- even if the balls aren't shot off in autonomous, they're still very valuable if they're in possession within the first few seconds of teleop before defense can be a factor.