Re: What won in 2006?
 

I have a hard time remembering that far back, but as I recall it, during SVR we either had no autonomous or an auton that pretty much sucked. I'd have to go back and look at those videos but I don't recall there being any strategy to lose autonomous.

We definitely did not have a very reliable autonomous until championships.

Re: What won in 2006?
 

I like how they fired balls from the corner of the ramp. That was really, really cool. Since they were surrounded on 2 sides by walls, they had nowhere to be pushed.

Re: What won in 2006?
 

I think the closest a team came to doing this was 111. Maybe some of the guys from WildStang can chime in as I am definitely just recalling this from a foggy memory.

If you think about the logistics of doing what you proposed, it ends up being quite a challenge.

-Brando

Re: What won in 2006?
 

LOL - Well, from what I see in the videos, it appeared that the result was a fortuitous sequence of events that worked beautifully (until the robot was beaten nearly to death by defenders).

The machine filled the goal like a grease gun seconds after auton was over (30 pts); returned to the driver station to be filled with the HP's initial balls and any balls the opposition had managed to score; then poured those into the goal during the combo scoring period(30-40 pts). Every shot counted, balls available to opponents were minimized, and opponents had no time to answer the points scored with the 2nd batch of 10+ scored balls.

The machine also appeared to have two "money shots". Two spots on the floor from which it was perfectly aligned to shoot 10 for 10. In contrast (that year was our rookie team), we poured endless hours into a 2 DOF turret that was "just a bit" less accurate than 10 for 10. ;) The team had convinced itself that defenders blocking shots would be a big problem. However, in those videos I saw clear evidence that we would have been far better off with a simple shooter and a better drive train. Some matches it took your (Poofs) driver(s) a little patience to get to the spots, but once the robot was in one, they pulled the trigger and for that batch of balls it was all over but the shouting.

Blake

Re: What won in 2006?
 

Blake, are these videos online?

Re: What won in 2006?
 

They once were easy to find.

Right now the The Blue Alliance has scores but no video.

The NASA Robotics Alliance is teasing me with a podcast at this location http://www.podcast.tv/video-episodes...l-4582699.html
that does seem to want to play on my computer.

Clever searching by someone might turn up a useful source.

I did find one video on the Menlo -Atherton team's site. It is of the final match of the 2006 SVR. In that match, a Poofs/alliance choice to stop an opponent during auton (instead of setting up for an immediate Teleop score), aggressive defense (and a bumper that fell off of a robot in an unfortunate location) combined to create an unusually low-scoring match for the 254 bot. In that match the Poofs & their allies chose to go for winning auton.

However, the opposing alliance still lost the match and the alliance with the Poofs won the regional. Several factors were in play. One was that when you are on defense you usually aren't scoring anything.

That video is here: http://www.youtube.com/watch?v=IWyoNY6CkHQ

Can anyone find any other 2006, Team 254, SVR (or other location) videos?

Blake

Re: What won in 2006?
 

In 2006, there was a muzzle velocity limit for shooting the balls (though they had a difficult time measuring it). If you did the analysis, there was a very specific launch angle that could score from the end of the ramp, to almost mid-field with the same velocity and shooting angle. This was a big enabler that year.

Re: What won in 2006?
 

We definitely did specifically tune the robot so that we had a few sweet spots to shoot from. As I recall it, one was obviously from on top the ramp, one was from the base of the ramp, another from the corners on either side of the ramp, and another about 10-12' out from the ramp. We did this by articulating the hood over our shooter between two positions.

Re: What won in 2006?
 

And the higher the exit point of the shooter, the greater the area of the field over which that angle could score.

Re: What won in 2006?
 

Found some (plenty) here http://video.google.com/videoplay?do...6592046251675#

One example is match 57 at 18:30 in that video.

You can find the 2006 SVR match schedule (to help you navigate through the multi-hour video) here: http://dev.thebluealliance.net/tbatv/event/2006sj

Just to stop fawning over the Poofs for a minute, the Poofs usually field a very good team in VRC and FRC (and probably in most competitions they enter); but I certainly don't think they sit around sipping ambrosia on Mt Olympus. Instead in this thread, I think they are a good example of winning by doing something other than just scoring points as soon as the rules allow.

You don't win if you don't score more points than the other alliance; but most well-designed STEM robotics games include more dimensions than just rushing to score. In particular, the path from the opening bell of an FRC match to a win isn't always a straight one. 2006 Aim High was game in which it wasn't *always* smart to shoot balls as soon as possible. Sometimes waiting for the right moment made more sense.

It doesn't take Olympian gods to think through subjects like this. All a team (like the original poster's) needs to do is to take a few minutes to stop and assess the games from more than one angle before settling on a strategy. The OP's plan to practice doing this sort of thing is a pretty good one.

Blake

Re: What won in 2006?
 

I want to say the angle was 28 to 31 degrees if you were shooting from very close to the upper size limit which we were. I think it was 28 if you ignored wind resistance, and then more like 31 after experimental testing and wind resistance was added in. (Trajectory physics is really neat to see applied).

This is a really good design exercise where shooting from a high point made it difficult to block, larger sweet spot for fixed angle, and several other positives.
Often though this made for a higher CG which was a big negative for going up that very steep ramp come bonus time. As this thread was looking for lessons, doing some sort of comparative analysis (Weight objective Table, House of Quality, Pro/Con table...) on the Low vs. High shooter would be very good. Team 67 form 2006 would be a good example of trying to find the unicorn solution. They had a neat design that in theory would have had an extremely low CG with a very high shooter, it just didn't work out that way in practice.
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Another important element from 2006 was how to handle a large group of balls. Many teams tried the large hopper with a feeder hole that resulted in ball jams. Trying to make a jam-proof system is much more difficult than it would initially seem. Many teams skipped the jamming problem al together and kept the balls serialized in a column. This allowed them to deliver balls extremely fast and accurrately.

Re: What won in 2006?
 

We definitely experimented with this early on. The goal wasn't to collect and shoot, but rather escape from a defender and shoot. We mounted a laser pointer to our turret and drove around while the turret tracked the goal using the camera. We found that the system wasn't fast enough to make the shots on the run at driving speed. We thought about adding in some predictive logic, but the turret wasn't fast enough. In the end without extra logic and keeping it relatively simple, it tracked great at longer distances and while sitting still. It worked pretty well when moving slowly and while getting pushed.

In auto we wouldn't shoot unless we were locked on to the light. In driver control, we had an LED stalk that indicated when the turret was locked on. This gave the driver full control.

In terms of trajectory, like many teams we had a hood that rotated to change the angle of the shot. We found that when close to the goal the angle had to be large and it decreased as we moved back. Then at some point the angle had to go up again to make the shots while the ball was coming down. We created a lookup table with the perfect angle at various distances and did a linear interpolation between the points. Using the camera, the robot calculated the distance using trig and adjusted the angle based on the lookup table. It worked pretty well for the most part.

Re: What won in 2006?
 

Thanks for the help all!

The end result of the session was 'the team' choosing to focus on the side goals, rather than the main one. Everybody felt that it would be too easy to defend the main one, and too hard to reliably score on it. And somehow, they managed to analyze it such that they could score 18 points in each side goal for every six in the top. Beats me.

Don't worry, I set them straight :P

We watched a video of Einstein that year, and it really does go to show that you have absolutely no idea how the game will end up being played until competition. It was a great lesson for new members; something you can't communicate just by saying 'it doesn't work out the way you think it does sometimes'

Again, thanks.

Re: What won in 2006?
 

I don't really think giving up on the idea of strategic analysis is a lesson you want to teach your team.

Re: What won in 2006?
 

A quick low goal scorer with a large capacity could be a great asset. If all it does is play D and collect balls all match and then dumps them into the side goals in the last couple seconds (15s?) it could swing the game. Every ball you take out of play from the floor is a ball your opponents don't have. If I recall 322 did pretty much this exact strategy. I seem to recall them winning a regional.


Edit: Also don't underestimate how irritating 1 ball in the low goal can be... I think Aren will agree with this statement.