Midfield Collisions

FIRST General Forum
1

I want to put a warning out to everyone in design build mode, to seriously consider the autonomous midfield collisions that will be taking place. I know many of you will say “well it’s not graciously professional to intentionally collide in the game”. Well let me say that most of the seasoned teams out there are thinking the only way to pull off autonomous vision caps, or stop them - is to do it as FAST as possible. This means there will be robots going blazing speeds through the coarse with no one at the wheel to avoid a collision. Then to compound the problem, there are only 2 access points to traverse to the opposite side of the field. This means almost by default, this game will begin to boil down to the teams that have the design and guts to come flying through that opening at full speed with the intent to stop a vision tetra cap. So another thing to consider is your tetra gripper mechanism/arm may get attacked in autonomous by a bot traveling 12’/s or more, with no regard to your bots shape or frailties. Basically a computer doesn’t care. If the design thats coming after you is rigid you could be looking at some pretty serious damage before autonomous ends.

I know some of you are already brewing at the thought of this happening to your babies. But it’s going to be part of the game. So please build them tough and with low CG’s. The ref’s can’t protect you during autonomous. Everyone knows to go easy during manual, but it’s the “autonomous valley of death midfield collisions” and the vision tetra seeker stoppers during autonomous that will inflict the most damage.

If you plan to cap during autonomous and your drive or mechanism are slower than around 7 seconds to complete the cap. It’s very easy to make the kit chassis stop you. And you WILL get hit with no regard to front/back or sides. So if you’re holding a tetra up 8-9’ in the air you better do some good scouting before you try.

Also I’m very concerned for the electronics from the kit. I don’t know how many Autonomous pounding’s they’re going to be able to take. If you decide to shoot the gap, and so does the opposing team. And you both meet midfield going 12’/s thats a 24’/s collision. Parts will go flying, batteries will come out. PWM’s will pop loose. Arms will swing wildly and twist. Be careful about your choice of autonomous.

You can’t blame anyone for using this method either. It’s logical to stop the best cappers as fast as possible. With the equipment given in the kit, it’s quite easy to do. Although the teams that choose to do this may have a short life span. I predict many of you will decide your arm isn’t working out and it’s more of a CG risk to keep it, then switch your strategy to a defensive chassis. Before you know it, the only teams left capping will be the ones who heeded this advice, or were thinking of it all along.

I’m going to add a poll to prove my point.

2

I fully expect auto mode to be aggressive. Auto mode comes with it a different set of ROE. I’ve considered a lot of auto moves aimed specifically at stopping teams from capping a vision tet, including running the bot at speed through all the possible tet locations, running circles around the center goal at high speed and generally turning my bot loose on the field.

Is it GP? I don’t know exactly. I’m also not sure just how the rules apply to auto mode. As Dan said, the computers don’t care, and the ref’s may not start throwing flags for robots acting aggressively during auto mode. I’m not out to damage anyone, but at the same time, I am out to win. Keeping the other teams from getting a vision tet could be a deciding factor. The rules say no high speed ramming. But is this a case of ‘punching the air, and if you happen to be in that air it’s not my fault’? I’m really not sure. Should the whole 2:15 of the match be reffed the same from a ramming/aggressive play standpoint?

-Andy A.

3

I’ve said it before … and I’ll say it again. I will be very surprised if more than about 1%of all robots (maybe 10 of around 1000 teams) will have the capability to consistently acquire AND score the vision tetra during autonomous. Please prove me wrong … but I am skeptical. IMO there are several productive strategies that could be chosen for autonomous and that is what I expect our team to focus on. Also, as a referee, I will do my best to enforce the rules as written and as instructed by FIRST :mad: . You may be asked to disable an “overly aggressive” autonomous program to avoid penalties and/or DQ … yes … even in autonomous mode. :wink:

4

i garuntee there will be several teams who can cap the center goal with a vision tetra despite virtually any opposition. however, i will also say that many many more teams will attempt to make robots like this and fail. auton may be the most important 15 seconds of the game, but the robots who are designed specifically for auton will generally fail. we cant forget that no matter how good an auton mode is, the opponant can always catch up in driver mode.

5

Stu,
A few weeks ago I would have agreed with you but I think the camera and software are going to make a lot of teams “auto ready” this year. For that reason I believe the number is higher. Still less than 10% of the teams will be effective in collision avoidance and accuracy. (IMHO)

6

“If you can’t do something cool, like cap tets in auto, you can at the very least ruin the hard work of others by ramming them into submission.” - The Prevailing Attitude

I happen to think there is nothing wrong with that attitude, and I intend to play both sides of the game well. The real challenge comes when you starting blocking the blockers…

7

Scout so that you’re not in doubt!
Know the autonomous programs of all of your opponents and alliance partners for every match so that you can take evasive action and avoid collisions. Program so that you have a couple of switches to change up the autonomous in advance of setting the robot on the field. For instance, if you and a partner both have a center-capping program during auto mode, defer to the more consistent capper by flipping a switch that allows you to cap a side goal or drop a hanging tetra.

8

Wow! You mean that simple little boxes on wheels, that can’t do anything else in the autonomous period except drive around (which they can do just by building the kitbot), might actually be able to play a very important role by protecting their vision-tetra-capping-capable alliance partners from opposing onslaughts?!!? Just drive really fast from the starting position to one of the two “channels” between the middle goals, and patrol there, block the opponents efforts to disrupt the alliance, and enable your alliance to score points during autonomous! And maybe if the simple little box on wheel teams wasn’t “quite there” with their autonomous software, a vision-tetra-capping-capable alliance partner that wanted them to fulfill that role might even be able to just give them the simple autonomous routine that they needed while they were at the competition! That seems like a pretty cool idea! Who’da thunk o’ dat?! :rolleyes:

9

I think that is really wishful thinking. Last year, my team was almost always the most friendly and willing to interact out of all the teams we played with. There were numerous oppurtunities where we could have benefitted (and vice versa) from people from other teams helping with software, yet very little happened. One programmer from another team did help out a bit, but the code he gave us was mostly useless because we decided it was too risky to try it without testing it.

Sure teams can lend each other spare parts and give each other advice, but I think its pretty unlikely that you will see many teams reporgramming other teams bots in the 1/2 hour or so that they have to prepare for matches.

10

Sorry if I’m coming a bit late to the party. I was out in the alley with a group of weirdos muttering about Amethyst colored glasses, hexagons, and Beatles albums while you were thinking up all this stuff, so I might be a bit behind the curve.

11

I think it’s possible, but very hard indeed. The problem comes with having time to test it.

12

Yea, I guess so. I must have been daydreaming. I realize that giving them

{CMD_DRIVE, 8500, 0, 0},
{CMD_TURN, (-1500), 50, 0},
{CMD_WAIT, 1000, 0, 0},
{CMD_DRIVE, 0500, 0, 0},
{CMD_WAIT, 1000, 0, 0},
{CMD_DRIVE, -1000, 0, 0},
{CMD_WAIT, 1000, 0, 0},
{CMD_DRIVE, 1000, 0, 0},
{CMD_WAIT, 1000, 0, 0},
{CMD_JUMP, 4, 0, 0},
{NULL, 0, 0, 0}

in a little text file would be too hard. :ahh:

-dave

13

Mr. Lavery, if you have the guts to take that from some stranger’s hands (regardless of the strangers intentions or background), drop it into the robot you have worked for 6 long, hard weeks on right before one of the maybe 25 actual matches your robot will play, you are a braver man than me.

14

That is what practice fields are for.

15

I have two plans for teams not having much luck with their cameras, both involving use of gyros and encoders. Your first option is to have your autonomous dedicated to blocking opposing blocking bots (Obviously I “borrowed” this idea). This is a good plan because the very good teams will likely have camera autonomous and will find you to be a valuable partner. The other plan is to have an arm with an aluminum tetra shape on the end, and two three way switches, one to select your starting location, and the other to select a goal which your robot will then drive to and put its aluminum tetra on top of for the duration of autonomous (It would be a part of the arm, not something it sets there then leaves obviously). Not only is this a more GP way of blocking than simply careening about with the intent of destroying, but it should also be moree effective. If you were really good you could even have a giant folding arm that covers all three goals :ahh: .

16

One of our many strategies in 2003 was to approach our partners, well in advance, to help them with their Auton code and any mechanical issues.

Maybe we just got lucky, but we found many teams that appreciated the programming help. They ended up with permanent code they could use and we had a better partner.

We feel that was a major factor in our success at the 2003 Championship. Also our team went home knowing that we had helped many teams over the course of the year. Overall a great feeling.

17

Robots that can tap the vision tetra in autonomous mode are going to be very very rare. 1% might be too low a number but most regionals will only have one or maybe even no robots that can do it. That being said, its a huge advantage and is well worth that alliances time to protect the robot that can. Only two robots can run through the sides during autonomous and try to stop the vision tetra bot. My guess is that the vision tetra’s two partners will also rush through the two gaps stopping any opposing robot from doing the same. You just have to hope you line all your robots up correctly so that it all works out. Its going to be tricky.

18

We are buildign to take the hits, and dishout more than our fair share in auto. we had thought abotu mounting the controler on a foam pad or somethign along those lines to prevent bad jaring.

19

Yeah. I know it has been noted that they actually give you a higher weight limit this year to accomplish way less. I think this is partly because they realised there were too many tasks last year, but also as they repeatedly emphasized at kickoff the game this year is going to result in a lot of colisions. Beef up your bot. (wow thats a catchy phrase)

20

A fact:

You do not have to shoot the gaps to block the center goal (or any goal, for that matter) in autonomous.

A question:

What is faster: Finding a vision tetra, picking it up, finding the goal, moving to the goal, capping; or driving straight about 17’ and placing an arm above the goal?

-Paul