Is your robot defense ready?

[RonnieS]

I don't know if it is just me...there are a lot of robots that I don't believe are ready to have defense applied to them. Especially seeing how this year should be a defense heavy game (basically it will be). Is this just me or do you see it too??::rtm::

[nuggetsyl]

I could not agree more.

[waialua359]

Absolutely agree.
Team 25 showed why they were the best in 2006.
Lots of great shooters that year, but only one Team 25.

[RonnieS]

I could not agree more.

I remember about week 3 or so I saw a team post a video of a "shock" type device that let their intake move side to side a fair amount and still maintain functionality, that will be key.

**Intake down, robot drives into it, your gunna have a bad day** :eek:

[Exla357]

Our eight-wheel tank drive has been able to push every robot we've ever encountered over the past 2 years out of the way, which is why we keep using it. We've got a similar set up this year, so as a driver I'm not at all worried about being pushed around. Blocking, on the other hand? Well let's just hope there aren't any goalie bots at Salt Lake or Denver :P

[nuggetsyl]

Our eight-wheel tank drive has been able to push every robot we've ever encountered over the past 2 years out of the way, which is why we keep using it. We've got a similar set up this year, so as a driver I'm not at all worried about being pushed around. Blocking, on the other hand? Well let's just hope there aren't any goalie bots at Salt Lake or Denver :P

I think us and truck town would like to accept that challenge.

[magnets]

I'm not too concerned about getting pushed around or breaking our attachment, but I'm actually worried about breaking another robot. We've got a big heavy catching thing that expands around our robot that won't break. If we go full speed into a robot's intake, there are several I've seen on here that I'm sure we'll break right off. We're making sure to bring our intake in if it's not in use when we play.

[WaterClaw]

With you on this. With an entirely open field, I think many teams fell for the illusion that this would be an all offense game. In reality, the best strategy would involve teams playing defensively for two thirds of the match as I see it.

[Sean Raia]

With you on this. With an entirely open field, I think many teams fell for the illusion that this would be an all offense game. In reality, the best strategy would involve teams playing defensively for two thirds of the match as I see it.

Yup. The team that wins in auto will simply have to play defense to ensure the win.

[nuggetsyl]

Yup. The team that wins in auto will simply have to play defense to ensure the win.

I disagree.

[BBray_T1296]

Yes. All of our perimeter protrusions are structurally reinforced with 1"x2" box tubing (1/8" wall and currently not cheese-holed either) with the pivot of the intake made from 3/4" diam steel axle. We spared no weight in protecting our attachments

[Abhishek R]

Yup. The team that wins in auto will simply have to play defense to ensure the win.

Auto doesn't give you a big enough lead to ensure a win by just playing defense there on out.

[BBray_T1296]

Auto doesn't give you a big enough lead to ensure a win by just playing defense there on out.

Unless the defense is summed up by a shutdown goalie bot that thwarts ~2 of your auto balls and a large percentage of teleop shots

[JohnSchneider]

Auto doesn't give you a big enough lead to ensure a win by just playing defense there on out.

You mean If I'm up by 5 after auto I haven't already won?

What do you mean first round sort is assist points not auto points? *grumble*

[Exla357]

I think us and truck town would like to accept that challenge.

Did I mention the drop center? We'll see you in St. Louis :cool:

[jvriezen]

If the red ball (or 2 or 3) is on the floor, and two blue bots can take turns hitting it (or hitting red bots trying to pick it up) to keep it on the floor and out of possession by red bots-- and one blue bot can make cycles without ever putting the blue ball on the floor (or holding it precariously in front of itself) then blue can win (albeit with less assists than they might like.)

I think a very competitive bot design is one that can get loaded in a secure hopper above the frame by a human (bot preferably not needing to be stationed at the field wall to still reliably receive), then truss toss and catch in its own hopper reliably (I know, no catch points for that) and then score, preferably 10 pts.

This bot can score 20 pts (and one assist -- since a solo run is one assist) on very fast cycles with low risk of loss of ball control, with the only effective defense being bots getting in the way and/or playing goalie. The bot's two partners can play full on defense- taking turns bumping the ball in the wrong direction and significantly slow down any cycle strategy that puts the ball on the floor to pass or where its easy to have a bot lose the ball via a strong hit due to insecure possession.

All three human players in alliance station can speed up cycles -- one at pedestal, one at corner and one at inbounding location -- ball is tossed from player to player to inbound as quickly as possible.

As long as the team is not too far behind after auto, it should be able to get/keep ahead with a robust, fast, low scoring cycle against a largely disruptable strategy that puts the ball at high risk of possession loss.

The top teams/alliances will have full control/carry-possession of their own ball and will control (but not possess) their opponents ball as much as possible. If you can't guarantee a reliable CATCH or a reliable self or human catch or human catch after a TRUSS, its probably not going to be worth doing the TRUSS, if your opponents are playing smart.

[xXhunter47Xx]

Unless the defense is summed up by a shutdown goalie bot that thwarts ~2 of your auto balls and a large percentage of teleop shots

Truss shots yo. There's no way you have a blocker that's within the height requirements that can block the parabolic arch of a truss shot.

[Abhishek R]

Truss shots yo. There's no way you have a blocker that's within the height requirements that can block the parabolic arch of a truss shot.

Height requirements in the goalie zone?

[Bob Steele]

All three human players in alliance station can speed up cycles -- one at pedestal, one at corner and one at inbounding location -- ball is tossed from player to player to inbound as quickly as possible.



I thought there would be only one human player in the alliance station. Two are stationed up by the truss in those positions. I also note that human players cannot pass the ball between each other from station to station. Now... that was assuming human players were dispersed on the field and not all behind the alliance area.

Anyone else want to chime in on this? Can an alliance use all of its alliance human players in the drive station area? Would you want to?

G8
Each TEAM member must be in designated areas:

COACHES and DRIVERS must be in the ALLIANCE STATION and behind the STARTING LINE.
HUMAN PLAYERS must be either in one of their HUMAN PLAYER AREAS or in the ALLIANCE STATION and behind the STARTING LINE.

G38
HUMAN PLAYERS may not pass the BALL to a HUMAN PLAYER in another HUMAN PLAYER AREA (passing the BALL within an ALLIANCE STATION or HUMAN PLAYER AREA is permitted).

[BBray_T1296]

Truss shots yo. There's no way you have a blocker that's within the height requirements that can block the parabolic arch of a truss shot.

If they can never complete a cycle (blocked in the high AND low goal) all you get is 10 points (20 for catch).

John is right though, assist points win 1st seed

[xXhunter47Xx]

Height requirements in the goalie zone?
yeah but that's goalie zone, blocking a high goal shot or low goal shot. A truss shot is in the middle of the field, not in the goalie zone. You can get 10 points for shooting a truss shot even if the cycle is not completed.

If they can never complete a cycle (blocked in the high AND low goal) all you get is 10 points (20 for catch).

John is right though, assist points win regionals
The point of me saying that is that a goalie cannot effectively block a truss shot, meaning it's not exactly effective to do hot zone auton with all 3 balls, move forward, and then in teleop shutdown the goals. Truss shots can give you the same amount of points as a high goal shot alone.

[TikiTech]

I'm not too concerned about getting pushed around or breaking our attachment, but I'm actually worried about breaking another robot. We've got a big heavy catching thing that expands around our robot that won't break. If we go full speed into a robot's intake, there are several I've seen on here that I'm sure we'll break right off. We're making sure to bring our intake in if it's not in use when we play.

We figured this could be an issue and went with 1/8" - 1"x2" tubing on our collector. Just in case, we made a second one to bring as our withholding allowance. In addition we really worked hard on making our frame and drivetrain very robust. We plan on playing the middle and hitting hard too! And you definitely have to bring in those intakes when not in use..

Good luck to everyone!

Aloha

[Sarakiro]

I remember about week 3 or so I saw a team post a video of a "shock" type device that let their intake move side to side a fair amount and still maintain functionality, that will be key.

**Intake down, robot drives into it, your gunna have a bad day** :eek:

1676 recommends some steel cable and a solid steel bar where applicable... :)

[RonnieS]

Yes. All of our perimeter protrusions are structurally reinforced with 1"x2" box tubing (1/8" wall and currently not cheese-holed either) with the pivot of the intake made from 3/4" diam steel axle. We spared no weight in protecting our attachments

Just because you make something very solid does not mean it couldn't possibly be bent. Think, if a robot hit this arm at 17 fps and it gets bent, will it still function?

[wesbass23]

yeah but that's goalie zone, blocking a high goal shot or low goal shot. A truss shot is in the middle of the field, not in the goalie zone. You can get 10 points for shooting a truss shot even if the cycle is not completed.


The point of me saying that is that a goalie cannot effectively block a truss shot, meaning it's not exactly effective to do hot zone auton with all 3 balls, move forward, and then in teleop shutdown the goals. Truss shots can give you the same amount of points as a high goal shot alone.

You can only get a max of 20 points (truss and catch) before actually scoring the ball. So if you never complete that cycle you will max out at autonomous plus 20. It is entirely possible to to get ahead in auto and never have to score again to win.

[Daniel_LaFleur]

I truly believe this will be the year of the broken intake.

Most of the RI3D style bots must extend their intake before shooting. With all the defense that will be played this year, I see many intakes getting damaged.

I hope teams bring spares.

[PandaHatMan]

Our team is definitely ready for defense-heavy matches. For wheels, we have 6" diameter, 2" wide blue nitrile wheels with 3-CIM ball shifters from Vex Pro. The top speed is around 17 feet per second. Crossing the field (driving 45' takes 3.25 seconds). We can push last years robot sideways.

Check out our reveal video (http://www.youtube.com/watch?v=zfgvXcCyOnI).

[Caleb Sykes]

I thought there would be only one human player in the alliance station. Two are stationed up by the truss in those positions. I also note that human players cannot pass the ball between each other from station to station. Now... that was assuming human players were dispersed on the field and not all behind the alliance area.

Anyone else want to chime in on this? Can an alliance use all of its alliance human players in the drive station area? Would you want to?

G8
Each TEAM member must be in designated areas:

COACHES and DRIVERS must be in the ALLIANCE STATION and behind the STARTING LINE.
HUMAN PLAYERS must be either in one of their HUMAN PLAYER AREAS or in the ALLIANCE STATION and behind the STARTING LINE.

G38
HUMAN PLAYERS may not pass the BALL to a HUMAN PLAYER in another HUMAN PLAYER AREA (passing the BALL within an ALLIANCE STATION or HUMAN PLAYER AREA is permitted).

Can you put all of your alliance members in the drive station area: absolutely. The rules you quoted answer this.
Would you want to do this: I wouldn't.

In my mind, there are some good plays that could involve human players in the far human player areas. Also, if you have any robot that is planning to throw the ball, you should have a human player in each of the far zones in case the ball goes out of play.

The only scenario in which I would feel safe putting all 3 human players in the drive station area would be if my alliance did not plan to ever throw the ball during the match. You might (being optimistic here) be able to save two seconds by passing the ball between players in the drive station area. However, there is more potential chaos involved by doing this. What if a coach gets in the way of the pass? What if an opponent's just-scored ball flies in and hits the ball that is being passed? Then your alliance waits for 10 seconds as the ball bounces around out of your reach until a volunteer gets the ball for you and returns it to the human players. In my mind, it's just not worth the few seconds saved per match to take one or more human players out of the far zones.

[Boe]

1676 recommends some steel cable and a solid steel bar where applicable... :)

No need for heavy steel, just need a few pieces of polycarb
http://www.fightingcalculators.org/blog/build-update-day-27-anger-frustration/
:)

[Samwaldo]

Our solution to defense :
- 3cim vexpro single speed, single reduction gearbox
- 4 inch wheels
- 1/4 clearance.
- EXTREMELY low center of gravity.

We proved at suffield shakedown and in our shop, we have both the speed and torque. When we were at suffield, we didnt realize how much defense would be played while waiting for your turn with the ball. Glad we prepared to be defense though!

[IVAN]

I expect to see alot of hit and run D

[Wayne TenBrink]

With all the overhanging appendages and high speeds, I hope the referees strictly enforce the "contact inside the bumper zone" rule. Breaking your own bot when you run into somebody is one thing. Trashing the innards of the bot you hit is quite another.

[mwmac]

I thought there would be only one human player in the alliance station. Two are stationed up by the truss in those positions. I also note that human players cannot pass the ball between each other from station to station. Now... that was assuming human players were dispersed on the field and not all behind the alliance area.

Anyone else want to chime in on this? Can an alliance use all of its alliance human players in the drive station area? Would you want to?

G8
Each TEAM member must be in designated areas:

COACHES and DRIVERS must be in the ALLIANCE STATION and behind the STARTING LINE.
HUMAN PLAYERS must be either in one of their HUMAN PLAYER AREAS or in the ALLIANCE STATION and behind the STARTING LINE.

G38
HUMAN PLAYERS may not pass the BALL to a HUMAN PLAYER in another HUMAN PLAYER AREA (passing the BALL within an ALLIANCE STATION or HUMAN PLAYER AREA is permitted).

IMO, an alliance that chooses to leave one human player area empty is taking a large risk especially if one of their balls leaves the field on that side as it would introduce a longer delay in the ball being returned to the nearest human player.

[Max Boord]

Our team takes a different approach to dealing with defense:
1. 20 fps
2. Mecanum
3. 3/4 inch ground clearance
4. 8 square inches of tread jammed into the ground with pnumatics.(anti-push feet)
5. A 6 cim powered arm called a "shooter" that defends the entire inside of our chassis. If a mechanism enters our chassis that mechanism may exit the field at high speed. (Or at least be persuaded into an upright and locked position).

[cmwilson13]

Our team takes a different approach to dealing with defense:
1. 20 fps
2. Mecanum


1 and 2 are exclusionary from my experience you may be geared for that but i highly doubt you even approach that speed with Mecanum.
if so id love to see a video

[pfreivald]

I believe the winning alliances will have robots wherein the ball rarely if ever touches the ground.

Otherwise, defense will likely school you if played well.

[JamesCH95]

Our team takes a different approach to dealing with defense:
1. 20 fps
2. Mecanum
3. 3/4 inch ground clearance
4. 8 square inches of tread jammed into the ground with pnumatics.(anti-push feet)
5. A 6 cim powered arm called a "shooter" that defends the entire inside of our chassis. If a mechanism enters our chassis that mechanism may exit the field at high speed. (Or at least be persuaded into an upright and locked position).

I second seeing a video of a mecanum robot geared for 20ft/s. Unless you have a crazy drive motor setup you're going to have a hell of a time getting to 20ft/s

[RonnieS]

How many people actually have to stop and/or lower intake to shoot? I guess when we designed ours to stay in the frame the whole time I didn't realize how big of a problem it would be for people if not kept inside! Oh snap::safety::

[JamesCH95]

How many people actually have to stop and/or lower intake to shoot? I guess when we designed ours to stay in the frame the whole time I didn't realize how big of a problem it would be for people if not kept inside! Oh snap::safety::

I would guess 1/4-1/3 of reveal videos show teams that deploy their intake, or some other mechanism, before they shoot. That's the impression that I get anyway.

[Tom Line]

With all the overhanging appendages and high speeds, I hope the referees strictly enforce the "contact inside the bumper zone" rule. Breaking your own bot when you run into somebody is one thing. Trashing the innards of the bot you hit is quite another.

I'm concerned about that as well. Large hammers swinging outside the bumper perimeter, intakes outside the bumper perimeter. I also hope that the refs are keeping a VERY close eye on intentional damage. Playing good solid D does not equal intentionally taking full speed runs at other robots and slamming into them.

[pfreivald]

Playing good solid D does not equal intentionally taking full speed runs at other robots and slamming into them.

It can, though--and as long as the contact is all inside the bumper zone, it's entirely legal.

[JamesCH95]

An interesting hypothetical situation would be: a defending robot rams an offensive robot and the defensive robot skewers itself, and become disabled, on a mechanism deployed by the offensive robot. Is that a foul on the offensive robot for contact inside the bumper zone? Is it a foul on a defensive robot for trying to incur a foul? Is it nothing because the defensive robot got what it was asking for by charging a deployed mechanism?

[E Dawg]

I fear for the structural integrity of anything that extends outside of the standard frame perimeter. That includes the tall blocking mechanisms on goalie bots.

[Andrew Schreiber]

I would guess 1/4-1/3 of reveal videos show teams that deploy their intake, or some other mechanism, before they shoot. That's the impression that I get anyway.

Wait, teams showed everything off in their reveal videos? :rolleyes:

[JamesCH95]

Wait, teams showed everything off in their reveal videos? :rolleyes:

Some fairly obviously needed to get their collector out of the way.

Smart-arse :p

[Andrew Schreiber]

Some fairly obviously needed to get their collector out of the way.

Smart-arse :p

We do? ;)

[Steven Donow]

We do? ;)

Not always ;)

[jijiglobe]

I think that teams can get around defense fairly easily by passing to their human players who can pass to another robot on the alliance. This may mean passing backwards across the field but its a lot of bonus points if carried out properly. It will also be really hard to block truss shots because they can go anywhere (even backwards over the truss) and will be incredibly hard to block. Auton points definitely won't be the only factor but they make a big difference.

[seanthompson]

You don't get points for passing over the truss backwards, only forwards. Two defensive robots on one alliance will seriously clog up the field, and most of the shooters won't be able to pass/shoot over a 5' wall that is right on their bumper. As long as the defender can stay in front of the robot with the ball, they have effectively stopped all offense for the opposing alliance. And a robot that has two defenders on it will have a lot of trouble making a controlled pass to another teammate. Personally, I think that there could be a lot of boring to watch, defensive matches. On the flip side, the strategies that teams come up with will be really cool to see in action, if they work.

[Caleb Sykes]

You don't get points for passing over the truss backwards, only forwards...

Please quote the rule that says this.

[Steven Donow]

Please quote the rule that says this.

Per section 3.1.4:

A BALL is considered SCORED over the TRUSS if a ROBOT causes a BALL to pass though the infinitely tall plane that is bounded by the top of the TRUSS and the TRUSS POLES toward the ALLIANCE’S GOALS (e.g. a red BALL towards the red GOALS). This plane is depicted in yellow in Figure 3-3.

[Caleb Sykes]

Wow, I have read the rules through and through multiple times, and I still managed to miss that point. Not that it should come into play very often though. Regardless, one of the most important things to know about a game is how points are scored, so I thank you guys for showing me that point.

[zinthorne]

We have to lower our intake too shoot, but i am not too worried about it, because it is well supported by the frame, and is almost all nearly 20" off the floor. I also think that most robots will be able to avoid their feeder systems being broken with driver practice, because they will know when to lift the arm better.

[rcmolloy]

As I have heard time and time again from coaches and others...

"Offense wins games (matches), defense wins championships."

With that said, we're 100% ready.

[jijiglobe]

While it makes sense that it would be easy to defend robots from passing to each other but there are more options. A fast turning drive train would be able to turn to one of the human players and pass to them very quickly as it would be much easier for a human player to catch the ball than another robot. This means that they can turn and pass quickly without worrying about it too much. The human player can then pass to another robot and I imagine it would be really difficult to block the opposing human player as they have a very fast and versatile drive train along with a shooter with a huge range of shot types.