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Re: Robo-Cross (B)

Posted: August 22nd, 2008, 9:31 am
by Pleiades
It's for B. I dont really like the coin thing though. I also dont really get it. The way it sounds is like they'll have 4 stacks of 10 pennies so you have to either pick them up with a claw and move them to the small goal or use a scoop to scoop them up into the little goal. I'm just worried i'll knock the stack over and have to go running after them. :lol:

Re: Robo-Cross (B)

Posted: August 22nd, 2008, 11:30 am
by captbilly
I hope the new rules make it a bit harder to get a perfect score. I think the top 15 or so teams at Natioals all got a max score and the medals were all based on the tie breaker. We were sometimes able to finish the event in just over 30 seconds, average 45 seconds and bad being 60 seconds. Of course the thing that I always feel is most important for the rules is that they make the event as "scientific" as possible, meaning that the results are predictable and repeatable.

Re: Robo-Cross (B)

Posted: August 22nd, 2008, 12:19 pm
by Pleiades
It will be a lot harder to get a perfect score this year. First of all, the coins seam very hard to pick up. I'll be very surprised if a team could get a perfect score in less than a minute. You cant just scoop everything into the goal this year if you want a perfect score. You have to put some stuff in one goal and the other stuff in the other goal. This will also add to the time.

Re: Robo-Cross (B)

Posted: August 22nd, 2008, 5:25 pm
by gh
Coins are not hard to pick up. Neither are index cards nor CDs. They're just to scare you. Take a file and a sheet of plastic. File its edge at an angle until it's razor sharp (sand it if you like, but keep it sharp), and it'll slide right under the coins if you drive fast enough. It's a lot of work, but that's what I did for Sumo Bots (NY trial), and I got under every single opponent I met. Apparently, it's even better than metal.

Re: Robo-Cross (B)

Posted: August 22nd, 2008, 5:42 pm
by Pleiades
I'll try that. Ok so i'm new to this event so could you tell me if this would work. I was thinking about putting an arm and a scoop on my robot. First I move the large goal into zone C so now my robot is in between the goals and the items. I then use my claw to pick up all of the items that go in the large box which is everything but the coins and 2 legos. Once i'm done with that I go use my scoop to pick up the coins and legos and dump them into the small goal. I then drive my robot into zone D. I have a feeling that would take A LOT of time. I dont really want to have to pick everything up with a scoop and then sort the stuff out. Or would that be better to do? Or i could just leave this event to my school's robotics team. I dont really want to though since they had from early october to early march to build a robot and they didnt get ANYTHING done. They told us a week before states that they dont have a robot. If we had a robot my team would have got 3rd place at state.

Re: Robo-Cross (B)

Posted: August 22nd, 2008, 6:21 pm
by gh
Arms are very slow. Scoops and buckets are always "Goins" to be better (SEE WHAT I DID THAR?) than claws or arms, so minimize their use where possible. I suggest that you use the doors method (in the wiki) to select what you pick up. It is MUCH easier to sweep things onto your scoop & bucket than it is to pick them up with an arm. Also, keep in mind that coins can be sorted out from other pieces pretty easily, since they always lie flat and have a lower profile than other pieces.

The Nationals winner (computernerd452?) got 14 seconds because it picked everything using just a scoop, dumped it into the can with a funnel, and the driver had a lot of practice. More time was spent aligning the robot with the can than on picking up pieces. Don't waste your time with a claw.

If it proves anything, scoops always dominated RR in Div. C, even this year when everyone said it was too slow.

Oh, just wondering, is there a picture or something of this year's field or does it look like last year's?

Re: Robo-Cross (B)

Posted: August 23rd, 2008, 5:58 pm
by WrightStuffMonster
Actually scoops did not dominate this year at nationals. I am pretty sure that I was the only one in the top 3 to use a scoop but I was quite a bit faster than others... Note cards are the only thing that is tricky to pick up. CD's and coins are pretty easy as long as you have something that is thin and sharp. I used 1/32 aircraft ply two years ago and it worked fine. The only thing that reliably picked up not cards for me was going really really fast and using photo paper with the smooth side up. I would bend the photo paper down so it was always contacting the ground and as long as the paper did not bend or rip after too many runs using the same paper I always got the note cards.

Re: Robo-Cross (B)

Posted: August 23rd, 2008, 7:37 pm
by gh
Considering the performance of your robot and how much margin you beat everyone else by, I think your bot is at least a fine example of a well-executed sccop bot (as well as overkill). Besides, if you won, then that's domination to me. :P

At any rate, the other teams weren't trying to pick up the items, so it's a moot point to say they didn't use scoops. :D

Re: Robo-Cross (B)

Posted: August 24th, 2008, 10:40 am
by WrightStuffMonster
In the scioly robot event I think that overkill is a very very good design philosophy. I ascribe to the 'more is never enough' school of thought and it kinda helps out in a few ways. Fist of all my robot was pretty solid. None of the electronics were operating close to their limits and even though i put an average of 5 hours a week of practice in for a couple months I only had one electronic failure. The previous year i had made my robot out of wood and ebay electronics from hong kong and I could not go a day without something breaking. It is really nice to be able to take your robot out of the box at nationals and have no doubt in your mind that you robot is going to hold together and stuff is not going to start falling off or breaking. Plus it is nicer to work with high quality parts. Not only do they work alot better and more reliably but should they fail most of the repair centers are very nice and one replaced something that was past its warranty!! I bet you wont get that sort of service from the Tower pro people in hong kong. (thats what I used last year so I would know) The only big downer is that all that nice stuff really costs quite a bit of money and my robot had some inane current draws which necessitated a large battery.

Re: Robo-Cross (B)

Posted: August 24th, 2008, 10:55 pm
by Winkyeye
2nd place robot was a vex scooper. we were the only box mover in the top 3, although penncrest would've been in there had they not knocked out a tennis ball. I remember a lot of the robots were overkills but didn't perform the task in the best possible way. Our robot was simple, wooden frame with only 4 motors and 2 servos. since we salvaged parts from previous years' robots, we only spent around $150 on the robot, not including replaced parts and the remote controller. if you include all the parts we broke and had to replace, that number would be a lot higher haha.