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Unread 02-10-2012, 08:26
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[MCC] Minimum Competitive Concept 2005

I am skipping over a few years and going way way way back to 2005 for this MCC.

For those of you not familiar with 2005, the name of the game was Triple Play. You can find the historical rules and documents back here.

I am bringing this one up as it hase beena few years since we had a "unique" playing piece. Other than its weight, I felt the Tetra was an excellent playing piece.

The basic rules of the game were there were 9 pyramid shaped goals about 6 feet tall. Points were given for placing Tetras in the base (1), or on the top of the goal (3). Whichever color was on the very top of the stack at the end of the match owned that goal. Own 3 goals in a row, and you get bonus points (10). Also if all 3 robots were behind the starting zone, you get an additional 10 points.
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Unread 02-10-2012, 08:56
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Re: [MCC] Minimum Competitive Concept 2005

Was there a bonus for autonomous scoring/vision tetras?
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Unread 02-10-2012, 09:07
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Re: [MCC] Minimum Competitive Concept 2005

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Originally Posted by Taylor View Post
Was there a bonus for autonomous scoring/vision tetras?
There was, I can only recall one team ever doing it though...

My MCC would be a 2WD tank-steer chassis with a hook on a single pivoting 'shoulder' joint. The robot would be human-player loaded and score one tetra at a time.

Scoring tetras underneath the goals was virtually useless in 2005 (1pt vs 3pt, and no "goal ownership") so a robot following this concept would not be competitive at all.
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Unread 02-10-2012, 09:10
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Re: [MCC] Minimum Competitive Concept 2005

2005 MCC is difficult because all the end game required was a drivebase and as James said, scoring low was useless in a majority of matches.
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Unread 02-10-2012, 09:29
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Re: [MCC] Minimum Competitive Concept 2005

I guess it would probably be 330's robot. How can you get simpler than a single degree of freedom PVC arm?
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Unread 02-10-2012, 09:50
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Re: [MCC] Minimum Competitive Concept 2005

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Originally Posted by Chris is me View Post
I guess it would probably be 330's robot. How can you get simpler than a single degree of freedom PVC arm?
I love how your suggestion for MCC is one of the most elite robots of the year, and one of the World Champions. I also love that I really can't argue with you.

-John
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Unread 02-10-2012, 13:39
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Re: [MCC] Minimum Competitive Concept 2005

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Originally Posted by Chris is me View Post
I guess it would probably be 330's robot. How can you get simpler than a single degree of freedom PVC arm?
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Originally Posted by JVN View Post
I love how your suggestion for MCC is one of the most elite robots of the year, and one of the World Champions. I also love that I really can't argue with you.

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I would argue that there were at least 2 effective robots that were simpler.

In this picture, all three of 330's defensive wedges can be seen folded up. Yep, three of them. 2 retractable, 1 not.

I can't find any pictures on CD of the two robots I have in mind, so I'll try to describe them. Note that all three robots I'm talking about were on the winning alliance in L.A. 2005. All three were single-joint arms.

634, Van Nuys High School: Their tetra-stabilization device was a split claw that would do the same thing as 330's except by going around the far leg of the tetra.

69, HYPER: 4 wheels, single-joint arm. I don't remember the end of their claw.

Neither of those two teams had any sort of defensive wedge. I think I can think of a couple other teams with similar designs, but less success--I'd have to work at it, though.
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Unread 02-10-2012, 09:32
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Re: [MCC] Minimum Competitive Concept 2005

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Originally Posted by BrendanB View Post
2005 MCC is difficult because all the end game required was a drivebase and as James said, scoring low was useless in a majority of matches.
Oh, about the end-game, either you could have all three of your alliance's robots in the end-zone, or have them all out scoring a tetra, earning 9 or 19 points (adding a row). Even scoring a single tetra to break one of the opposing alliance's rows was a 13-point swing (you earn 3, and break a row of theirs, -10) so the endgame was not very important. If you could complete a row for your alliance and break a row for the other alliance you got a 23 point swing by scoring 1 tetra.

For example, we played some matches defensively with one tetra on board. Near the of the match we would drop that one tetra on the far-corner goal, typically breaking the other alliance's home row and completing a side-row for our alliance. Sometimes we either scored a diagonal or broke a diagonal row also, so this one tetra was almost always a 13-pt swing at a minimum, sometimes a 23-pt swing, and at best a 33pt swing. During the main time of the match it was pretty easy to trap or slow down other robots because the goals divided the field into controllable segments, so the opposing alliance's scoring ability was reduced.
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Unread 02-10-2012, 09:54
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Re: [MCC] Minimum Competitive Concept 2005

In autonomous you could score by
  1. grabbing a special vision tetra on the floor and scoring on a goal earned bonus tetras on corner goal(s), unfortunately not very much time to get this done, however, the vision tracking could actually be done before the match started.
  2. grabbing or dropping starting tetras hanging under each of the corner goals. Very easy to do.
  3. Scoring a tetra one robot on each alliance could start with.
Also, scoring under a goal did confer alliance owership, until a higher tetra was scored.
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Last edited by Mark McLeod : 02-10-2012 at 10:04.
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Unread 02-10-2012, 10:40
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Re: [MCC] Minimum Competitive Concept 2005

Quote:
Originally Posted by Mark McLeod View Post
In autonomous you could score by
  1. grabbing a special vision tetra on the floor and scoring on a goal earned bonus tetras on corner goal(s), unfortunately not very much time to get this done, however, the vision tracking could actually be done before the match started.
  2. grabbing or dropping starting tetras hanging under each of the corner goals. Very easy to do.
  3. Scoring a tetra one robot on each alliance could start with.
Also, scoring under a goal did confer alliance owership, until a higher tetra was scored.
Using the CMU2-cam in 2005 on the IFI board was a very difficult task, unlike using the web-cameras on the crio in recent years. One of the most challenging parts was that the lighting at every event was different, and the vision tetra could look white or green depending on how the light was hitting it and where your camera was positioned.

FIRST solved the problem in 2006/2007 by making the targets illuminated with cold cathods, but in my opinion anything that was "minimally competitive" had no use for the camera.
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Unread 02-10-2012, 12:11
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Re: [MCC] Minimum Competitive Concept 2005

This is a difficult one. While there were a handful of exceptions, there really was only one useful task in this game (scoring on top of goals). Contact defense was highly risky with the 30-point loading zone penalties and the fact that the best "defense" was often breaking opposing rows via "offense" (capping). The end game only gave points if the entire alliance was in the home area, and the reward was often far less than the potential gain of continuing to score in key areas.

Scoring the vision tetras was difficult, but knocking off the corner tetras was incredibly simple and still conferred (often temporary) ownership of a corner goal. Simply put, there was no reason not to knock off the corner tetra, and doing so freed up a >MCC robots to focus on other tasks (vision tetras, loading from auto loaders like 233, or scoring the one pre-loaded tetra). Also, this was relatively early in the "autonomous era" (started in 2003), so there were plenty of teams who sat and did nothing in autonomous.

The auto loaders were surprisingly difficult for many teams to load from, but the human loaders were easy (albeit much more time consuming).

Many teams made cumbersome arms/elevators designed to score on high stacks (and the taller center goal), often resulting in all of their scoring taking much longer and being much less reliable. In most matches, stacks didn't even accumulate that high to begin with. Focusing on scoring on shorter stacks and leaving the center goal (beyond the first tetra or two) to alliance partners may enable a simpler and easier to operate design for teams with limited machining resources.

A tetra manipulator with some sort of stabilization (even as simple as the passive devices on 217/229, 330, and 254) greatly reduced the amount of time required to score and reduced the odds of dropping a tetra.

Scoring multiple tetras at a time was a beneficial feature, but ultimately not a particularly important one. No need for a MCC to focus on this.

So, to summarize:
A robot capable of knocking off the corner tetras, human loading, and scoring on short tetra stacks with some sort of stabilizing manipulator. Obviously the drive-base should be reliable, easy to control, and reasonably fast. And the driver should avoid penalties!!
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Unread 02-10-2012, 13:44
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Re: [MCC] Minimum Competitive Concept 2005

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Originally Posted by Lil' Lavery View Post
This is a difficult one.....

So, to summarize:
A robot capable of knocking off the corner tetras, human loading, and scoring on short tetra stacks with some sort of stabilizing manipulator. Obviously the drive-base should be reliable, easy to control, and reasonably fast. And the driver should avoid penalties!!
I agree. A MCC robot would typically be a third member of an alliance. The strategy for our championship alliance was to only focus on scoring on half the field. We split that half amongst our three alliance partners. With our third partner (503) scoring on the rear corner and middle goals. 503 wasn't really an MCC machine that year, since we had them as the 4th best machine in the division and picked them with the 9th pick (non-serpentine draft).

But, they essentially performed MCC type tasks in the elims. Reliable drive base, human load, passive manipilator, capable of scoring on shorter goals.

Maybe my expectations of a MCC type machine are a little high. But, with the penalty rules the way they were...there wasn't much else you could do in this game if you weren't scoring to help your alliance.

Good topic. Minimum level for this game was probably a little higher than any of the games since then.
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Unread 02-10-2012, 17:10
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Re: [MCC] Minimum Competitive Concept 2005

Were wedges still legal in 2005?

If so, I vote for box on wheels and flip down wedges..

Regards, Bryan
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Unread 02-10-2012, 17:19
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Re: [MCC] Minimum Competitive Concept 2005

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Were wedges still legal in 2005?

If so, I vote for box on wheels and flip down wedges..

Regards, Bryan
They were only allowed in a passive manner; you couldn't intentionally tip someone with them. However, if you were placing a tetra going about your business and someone rammed you and tipped themselves, it's their fault.
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Unread 02-10-2012, 19:17
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Re: [MCC] Minimum Competitive Concept 2005

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Originally Posted by BJC View Post
Were wedges still legal in 2005?

If so, I vote for box on wheels and flip down wedges..
Legal, yes. Used to tip other robots over, red card. Which is, I think, why wedges have been illegal since 2006. http://www.chiefdelphi.com/media/photos/21301 shows a tie match in Archimedes QFs; this was the only 0-0 eliminations match (and might still be). This particular one was caused by red cards for tipping, as I understand it. The offenders both either carried wedges or had them built into their robot.

I do remember at least one Box-on-Wheels with a flip-down wedge on one end. No eliminations for it, and I seem to recall a number of penalties.

330 used theirs to keep other robots from interfering with scoring. Usually it worked. Then there was the one robot that had to be dealt with in another way... by lifting the tetra that we were picking up (one of ours, of course) and they had their wheel in. They started coming along with it, we put it down, and they didn't bother us like that again.
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