autonmous corner or center
 

How many people out there think people are going to use the center goal or the side goal during autonomous...It would seem that because you can just program your robot to go straight to the corner goal, that it would be used the most. And also the issue with the camara also comes to mind... buts thats a whole other problem.

Re: autonmous corner or center
 

As a team we havent decided, but I personnaly want to use the camera and get that perfect. Im sure many teams will be going for the high goal because it is 3 points, and if you can get those points and win the autonomous mode you get another 10 points.

Re: autonmous corner or center
 

Since this is my senior year and my team's 6th year in FIRST I would prefere doing the hardest part of the game. Come on, what could be cooler than robots shooting balls at high speeds in autonomous mode?

Re: autonmous corner or center
 

I agree with Scitobor here... Robot shooting with no way to stop it? Why not? ;)

Re: autonmous corner or center
 

I think our team has decided not to go for the center goal but myself and a few of the rookies are problably going to be building a separate cannon structure on the top of the robot that is operated almost completely separate.

Designer,
Cuog

Re: autonmous corner or center
 

but do you not think that many team will take the easy guarentee of 10 points with some type of dumping method. I'm am not anticipating very high scoring autonomous periods

Re: autonmous corner or center
 

Heh. 10 points. That's trvial.

There's a lot more hidden in this autonomous mode than you may think.

Re: autonmous corner or center
 

he's right. the real kicker of winning autonomous is the deffending first and offending last.

Re: autonmous corner or center
 

I am rather interested to see if anyone is going to be able to use the camera to score it does seem a lot easier than it was last year... As far as what my team will do I can't even begin to imagine, As we are rookies this year I'm sure it wont be too over the top, but Ive been fooling around with some ideas that would allow us to score both. One of my concerns on shooting for the Center goal is that even the slightest hit from another robot is going to throw off your aim and In autonomous mode (only 10 seconds this year) your not going to have much time to adjust and re-aim. which may mean you'll lose out on a given 10 points if you try to shoot.

The phases depend a lot on auton and winning / losing auton will have a lot to do with alliance strategy, It adds a strange new dynamic to scoring and it assures the defending will be the end all be all of pushing matches.


This game gives me a headache...

Re: autonmous corner or center
 

i agree with the fact that like last year, scoring the center goal in autonomous will be hard. but the reward for doing it could win you the rest of the match. will many teams be able to do it? well have to see.

Re: autonmous corner or center
 

Well, atleast seeing the center goal will be easier. My only concern is that both light arrays are the same color, so if a robot gets turned around, it could score in the OTHER goal. So far, GDC hasn't told us what happens when a robot scores in the wrong goal during auto

Re: autonmous corner or center
 

The way I've read the rules, I think they say balls scored in those goals count for the score of that alliance. Since opposing robots can score by being on the other teams platform, they'll probably allow robots to score balls for opposing teams too.

We hope to be able to shoot for the center goal in autonomous. Right now I'm more worried about being able to shoot the ball in the center goal in the Human controlled part, let alone autonomous.

Autonomous is going to be very fast this year. Alot of quick shooting and praying balls go into goals.

Re: autonmous corner or center
 

Scoring the center goal might not be as hard as thought. If there is a very dependable shot from human mode, you can always use a 'teaching' style auton mode to set up that shot.

I'd much rather use teaching styles or point to point moves than hand control of a robot to the camera. After working extensively with the camera last year before ultimately putting it aside in week 5, I think that it is easier to use the camera this year but I honestly cannot see an incredible number of benefits to do it other than targeting purposes.

I see more of a fail-safe mechanism and position to shoot from than moving shots from anywhere. If defended, most if not all mechanisms would probably be adjustable but human controlled for aim.

Re: autonmous corner or center
 

I think it will be particularly easy this year to score in autonomous mode. Unlike last year, when the vision tetras changed places every match, the goal is in the same place every match. And unless i missed a rule, you don't have to move out of the starting zone to score in auto mode. And since the starting zones are 5'x5' each, it gives a 28"x38" robot enough room to start out diagonally. So if you have a robot that shoots straight foreward, you just aim your robot at the high goal before the match starts, and then start shooting right when auto mode begins. As long as you've spent an hour or two ahead of time to make sure your robot shoots its balls at the right speed and angle, you don't have to worry about aiming and hopefully get an easy 30 points (40 if you count the ten for winning autonomous). I don't see vision being as helpful in auto mode as it can be in helping the drivers aim during the human controlled periods of the game.

Michael C.

Re: autonmous corner or center
 

i know that if 971 is shooting in auto, we'll be using the camera

Re: autonmous corner or center
 

i read there is a white light that is used to score the balls in the corner goals. would it be possible to track the corner goals using the camera?
I am asking because using dead reckoning to find the corner goals might prove to be difficult.

Re: autonmous corner or center
 

I think that with the cameras, there is potential for chaos during autonomous.

But, I guess it will all work out in some way :)

Re: autonmous corner or center
 

The corner goals are litterally right in front of you if you point your robot down field. Just point your and go forward. What's so difficult?

PS The camera won't track the corner goals, trust me.

PPS Listen to Tom, he's a bright guy.

Re: autonmous corner or center
 

My (entirely unofficial) interpretation of that: Balls are balls. If you hit their goal, they score points. Done deal.

Re: autonmous corner or center
 

Considering that many teams will use them for center goal shots, theres a potential for chaos during every period...

Re: autonmous corner or center
 

Very true, but humans will have a little more control, I see in autonomous all the bots going to similar or the same places trying to find the green, possibly quite a bit of collision. I guess that is where the bumpers come in!

Re: autonmous corner or center
 

It depends on what your robot is good at. If you have no mechanism for shooting, you won't try for the center. Our group has decided to focus on the corner goals, both in autonomous and in normal play.

Re: autonmous corner or center
 

All I know is that last year in Philadelphi, our camera locked dead onto MOE (Team 365) and their flourescent green shirts during the matches. They might want to consider what would happen if they get pelted with balls during the autonomous period! :ahh:

Re: autonmous corner or center
 

LMAO! That would be kinda funny, other then the not safe part. But yeah!

Re: autonmous corner or center
 

Be careful about aiming your robot. There's a rule against using "any measuring devices while placing your robot that are not a permanant part of the robot", last year I used my shoe (it's exactly 12"), but I suspect this year that won't be allowed. If the ref decides you've lined your robot up against this rule, he's free to move/turn it at his discretion.

Re: autonmous corner or center
 

Both goals being on the field should not be much of a problem, since it is unlikely that you will be pushed onto the wrong side of the field, and your robot will know what position it is starting in.

The green targets are roughly 10ft above the field, and if you are using Kevin's 2006 CMUCam code, you will be able to easily get the angle of your tilt servo, that angle becomes theta, from that you can do Tan(Theta) = (10/X) and solve for X. That reduces to X = (10 / Tan(Theta)). The field is 54' long, if you are >28ft away, you know that you are shooting onto the other side of the field.

It's not perfect, but it's unlikely that your robot will be pushed onto the wrong side of the field, and turned around. This is why it makes sense to have an onboard navigation system.

I’d really like to see our team design a bot capable of shooting into the center goal, the only real issue I can see is the hardware shooting device not being consistent enough to depend on it.

Re: autonmous corner or center
 

While at kickoff I asked Woodie if there were any concerns about missed shots at the center goal hitting the operators or the controls. He handed me a ball and told me to throw it at him as hard as I could... How many times does an opportunity like that come up?

Re: autonmous corner or center
 

The camera is absolutely esential to this game during both auton and manual mode. Thats the only way to constally keep track of the goal. Otherwise you would have to stop and postion the launcher so the ball goes into the hole. Think of doing this manually form over 30 ft away toward the other end away form you?
Realtime trig and projectile motion calculations!!!

Re: autonmous corner or center
 

Yes, the camara would be nice to use in the manual 2 minutes, but then you are relying totally on the camara. our team was thinking of something where the camara would give some kind of feedback, whether or not the position of the "cannon" would make the shot.

Re: autonmous corner or center
 

Center goal. All 10 in less then the 10 seconds. :D

I just don't know how to do it yet. :(

Wetzel

Re: autonmous corner or center
 

Then you have to constantly move it around until it locks on and this is pretty hard manually and very time consuming.

Re: autonmous corner or center
 

it's good to hear that so many teams are planning to use the camera this year. last year, a lot of people said that they we're not using it about a week in, and never touched it again. Now we just have to see who follows through. Look for an exciting auto mode this year!

Re: autonmous corner or center
 

The camera doesn't just have to be used to find the center goal, by finding the center goal you can dead reckon your robot to a corner goal. ;)

Also note: no robot camera will be able to see the white light inside the corner goals unless they get inside the goal. But then they get DQ. :ahh:

Re: autonmous corner or center
 

Well, that's what the acceleration and yaw rate sensors are for...

Good luck, start on that code as soon as you can 'cause 6 weeks comes up pretty quick.

Don

Re: autonmous corner or center
 

Exactly, it won't take much time to re-align the robot either. the CMUCam has quite a large viewing angle, 98% of the time, the camera will hardly need to move to re-acquire the target. The code plan I currently have in my head is to have a "shooting mode" if you will, and in this mode, any external change to the feedback sensors will call for a restart of the shooting mode. Any bump will have the cannon stop firing and wait until the camera re-tracks and configures the shooting device. The worry I have is if another robot it very tall and comes in front of the cannon while shooting, without touching our robot.

Re: autonmous corner or center
 

Now here's an interesting theory... using encoders, a gyro, and the camera (or other sensors), find your velocity, robot current facing, current distance from the center goal, and find a way to compensate for your movements so that you can hit the goal while moving at almost any speed. Any programming team out there feel up to the challenege?

I hope teams are remembering that there is a defensive aspect to this year's game as well. It seems everyone is ready to sit there and shoot at the goal, but that doesn't work so well when someone pushes you out of range.

Re: autonmous corner or center
 

i am no programmer, but i have talked to the programmers on my team, and it seems almost an impossible task to shoot while moving at a fast speed. One's camara would have to have the capability to move very fast with the cannon... but then one is sacrificing accuracy if one had to manually take the controls.

Re: autonmous corner or center
 

Our team has started looking at this, and we realized that all these new sensors are in the kit for a reason, and if you use them right, and if you have the range, you could nail the center goal going at about any speed, but impacts are a different issue. We are looking at ways to isolate our cannon from impact so it can stay steady while our bumpers take the jolts. All in all, it looks like a ton of fun! Lets get to it.

Re: autonmous corner or center
 

The great thing about defending first is that you can prepare for your attack and get a "fast break" with your back bot.

However, this is offset by the fact that the other team can prepare for the free period.

However (again), this is offset by the fact that in the free period most people will probably be trying to score, and you will be open anyway. Also (more importantly) you will already be down at your end of the field and won't have to waste :05 getting back.

Re: autonmous corner or center
 

Not only is it a programming nightmare (I say this in a good and bad way) it physically makes you much more likely to miss.

It seems to me that the most practical "moving while shooting" would be if you were already ligned up with the goal and going towards it. You could adjust the angle of your cannon at a more or less constant rate. As you move parallel to the midline, however, you have to adjust cannon angle *AND* cannon direction.

KISS

Re: autonmous corner or center
 

I'll take that challenge.

Re: autonmous corner or center
 

i don't know, but we might do it. it could definitely be an advantage.

Re: autonmous corner or center
 

We are going to try and keep constant track of the goal with the camera and then using its relative positon on the robot,the data it relays back, a couple of trig functions and projectile motion equation, to try to adjust the angle and direction of the cannon constantly.
I think the camera can do like 25 frames per second, right?
What worries me is how to compensate when being hit by other robots?

When your robot is just about to fire and another robot hits yours, there is no way to adjust the cannon fast enough to compensate that I can think of.

Re: autonmous corner or center
 

Hmm I'd like to point out a rule that may burst your bubble...

<S02> Muzzle Velocity - No ROBOT may throw a ball with an exit velocity of greater than 12 m/s (26.8 mph).
As a reference, a ball traveling at this velocity when leaving the ROBOT at an angle of 30º from
horizontal with no spin will travel approximately 35 feet. A robot that violates this rule will be
considered unsafe per <S01>.


Planning on shooting automated from your starting location may not fall within that guideline. The true center of the arena is 27 feet from the target and 13 feet from the wall. Shooting from the wall would then be a horizontal distance of approx. 30 feet. If the ball is launched at 30º with and exit velocity of 12m/s, it would peak at a horizontal distance of 17.5 feet away. Using 45º at 12m/s, it would peak at a horizontal distance of (around) 22 feet away, with a height of about 12 feet. This would give it a rough range of 44 ft horizontal. Which means it could very well be possible to get the ball through a 8.5', 30" goal with 12m/s. Of course my calculations are just using simple trajectory with no regards to drag.

Hmm. As I sought to prove that you cannot make the target from your starting position, I proved the opposite, not only can it be done, it's very possible. Well then, no bubble bursting for me. :ahh: Let the fun begin!!


With regard to the positioning of the robot, because you cant measure or anything, would it not be possible to just point it towards the center, tell it to turn Left and have the camera start searching in the general area of the light?

Simple solution no?



And forgive me for my completely inane post.

Re: autonmous corner or center
 

unless it sees the opponent's light first and fires there...

Re: autonmous corner or center
 

Whats bugging me is drag? Is it enough to affect the range(the balls are so light)? Even if it is off by one feet it could hit the rim and bounce off.

No problem, its good that I made you realize it's possible. (the cannon is not on the ground)

If your cannon is sitting on a turret(possibly the camera too) then you don't have to have the entire robot face toward the center goal. If your cannon has to face forward to start then just initialize it to turn like 60(or what ever is best) degrees toward the direction of the goal (with a turret or with out it) and then make you camera scan for the light.

Re: autonmous corner or center
 

Well I had doubts in the beginning. I thought corner scoring would be much more efficient and you'd be able to score there quicker. But after talking to programmers and other members on my team, I decided the center goal would be much better. Why? It's way cooler! Plus, our programmers are much more confident with the camera then they were last year. The way I see it, the corner is meant for inexperienced teams and as a backup. Cause let's face it, you can't have three robots firing at the same target at once, it won't work. The whole cannon idea is fairly new, which is nice because that puts a lot of teams on the same page. It will be a nice challenge, and I'm sure many teams will have great results.

Re: autonmous corner or center
 

Shooting from the start point is good idea, but you have to think about the max speed you can shoot. The distance between starting point and the goal is too far to shott. Isn't it? Actually, I haven't check the distance between two, so can't tell right now.

Re: autonmous corner or center
 

Well thats what I thought too, but it appears that in fact it could be possible. The only problem you may have is drag,


Hmm I wasn't clear in my other post about the "simple solution." I think if you tell your robot to turn left and then start searching, your opponents light would be behind you, making it almost impossible for the camera to grab the wrong light.

Re: autonmous corner or center
 

What's the maximum highest theoretical score during autonomous. I believe it would be 90 = 3 robots * 10 balls * all shot into the center goal. Obviously not likely -
in 10 seconds you probably couldn't get 10 shots off, and if all the robots were shooting at the same time they would interfere. While is seems easy to build a robot that could deliver 10 balls to the side goal, I don't think you can do this perfectly, so I'd imagine that even if an alliance has a robot that can deliver 10 points consistently to the nearest side goal, what do the other robots do? You may be shutting out another robot of equal capability.

What would be a typical high score in automode? I am guessing that an average alliance would have a robot that could score 10 low, another that could score 5 low in the far corner, and a shooter that could score about 3 high. so about 24 points.

If you build a robot that can score more that 5 high in auto,
or consistently deliver 15 points by some combination, you will be winning all your automodes.

Another thought, if you consistently can shoot 10 into the center during autonomous mode, opposing alliances that can't match your performance, may decide to disrupt you by programming their lowest scorer to simply interfere with you. There is no rule that says you can't play defense in autonomous mode!

Al that said, it would be way cool to build a self aiming cannon that would track, shoot and score on the run. If you developed that, you might want to sell the technology to Raytheon, which has been having some issues with the ABM program.

Re: autonmous corner or center
 

We are leaning toward the 10 "easy" corner goal points. But our programmers feel they could get a launcher to work. We'll see. For now we are working toward both goals.

Re: autonmous corner or center
 

I'm hoping towards the shooting during the auto, but i just hope accuracy will be perfected, and when it comes down to it, the winning teams will either be a team with 2 shooters and one pushing in the corners, or a team with 3 shooters... One just wont get you the points needed for victory I believe

Re: autonmous corner or center
 

im just thinking of one thing, the time limit.
10 seconds,
and really thats only 9 because the camera takes a second to boot.
then you have to count in the time it takes the camera to aquire the target.
then to aim
move into a shooting position, because the long shot would be very hard with the speed restriction.
and then unless your "cannon" has the ability to fire automatically or very quickly semi i dont see many balls getting out of it let alone accuratly.
i know last year 15 seconds wasnt nearly enough time to do the auton mode
i cant believe they cut it down to 10
at least they enlarged the memory so we dont have to completely rewrite the code again this year.

Re: autonmous corner or center
 

The camera will be active immediately after turning on the robot. It can find the green and communicate with the robot controller just fine while the robot is disabled. Your robot can enter autonomous mode and be ready to go with no camera-induced delay.

Traveling and aiming will still take time, of course, but that's not the camera's fault.

Re: autonmous corner or center
 

Good to know, but I still think 10 seconds isn't enough time to get more than four or so shots in the center goal. Some kind of rapid fire device that can load a constant stream of balls that don't interfere with each other could make it possible for a robot to score big during Auto-Mode. I'm not going to give up my idea yet (it's still in development), but it's based on a six-shooter revolver.

As far as the software side of it, a mathematical algorithm for calculating the launch angle and velocity shouldn't be too difficult. It's mostly just simple trig. I think the only variables we need to be concerned with are distance and velocity. For fast moving bots the "p" factor could come into play.

Re: autonmous corner or center
 

actually, when you introduce drag they become differential calculus equations