Sumo Bots C

[ichaelm]

I was talking about khouse.

[chalker7]

Last night there was an important FAQ related to the Sumobots impound posted to the national website. You can read it at http://soinc.org/node/276

[questionguy]

For the competition, does it take all six sessions. So if you win your first round, do you have to stay until your second round, etc. I am just worried that I won't be able to compete in any of my other events.

[chalker]

For the competition, does it take all six sessions. So if you win your first round, do you have to stay until your second round, etc. I am just worried that I won't be able to compete in any of my other events.

There is a FAQ on soinc.org that explains how the rounds work: http://soinc.org/node/684

[Flavorflav]

But the short answer is: no. You will have one session in which you compete in your preliminary bracket. Two robots from each bracket advance to the final bracket, which is usually held after all other events are complete. So you are committed for at most two sessions, one of which probably has no other events in it.

[lakeside]

Random observations from my regional tournament yesterday:

1) "The lighter of two bots wins" rule doesn't specify whether this weight is measured directly after the match or measured at impound. This rule came into dispute because one team had this massive aluminum plating rig that came off during their first match. This meant for the second match their robot was probably .5 kg lighter than its impound weight. Because of this, it lost by weight to another robot, even though it clearly weighed less, because it had weighed more at impound. The event supervisor ruled that the impound weight had to be used, so he lost. The rules seem ambiguous to me, so I'm not sure if that was the right ruling or not. If the impound weight is used, seems like someone could bend the rules a little by submitting a light robot, then adding their Claw of Death or whatever attachment they wanted between matches, and keep their beginning light weight. This leads to:
2) Working on robots between matches. The rules mention, "After impound, teams cannot modify their robot before the first match." which seems to me to imply it is OK to work on your robot after the first match, which is also what my event supervisor said to me. But the rules also say "If a robot is damaged during competition, teams may make repairs between matches." So are the modifications between matches limited to "repairs", or can I do whatever I want to my robot? And where is the line drawn between "repair" and "adding new features"?
3) People's robots were very well built, but they didn't seem to have much practice driving them. I was driving a lightly modified vex robot, which was basically just the example vex chassis with some weight stripped off of it, the gear ratios redone, and a basic metal wedge riveted on the front. Not exactly a high quality build. Its only strengths were its light weight and good balance of power and speed, but about 6 of the other 14 robots would've crushed it in a head-on fight. But in the two matches where I could tell my robot would lose head-to-head, was able to out maneuver them and flip them from the side. And it wasn't like my robot was faster or anything, the just let me get around them. I'm not sure why they didn't realize this. That went the other way too. Some teams would go straight at the other robot even though their robot was less powerful. And once they started getting pushed back, they didn't try to turn or get out of it at all, they just kept pushing the remotes harder and pointing the antenna closer to the robot, thinking that would somehow make their robot faster. But it didn't, since that isn't really how R/C works, and they were pushed out of the ring.
4) Do byes count as wins (for scoring)? I might be missing something obvious in the rules, but I don't think it specifies either way.
5) Pretty much every team that won a couple matches was using some variation of the snowplow/wedge, except for one team that had this awesome spatula-like device that shot out from under their robot, it would go under the other robot and leave the other robot stuck with its wheels spinning off the ground. Then they would just carry the robot out of the ring. It won several matches in very nice style, but then lost twice on weight because they couldn't figure out how to push the other robot out of the ring once they got it stuck. I'm not sure exactly what was propelling it, I originally thought pneumatics but those are illegal under the rules, so I'm guessing the just had some sort of motor rig within the robot. With a little modification they could've easily won the tournament. Hopefully we'll see more cool innovations like that at the state and national level.

Thoughts? Clarifications? Questions? How did other people's regionals go?

[Flavorflav]

My 2 cents:
1. Technically, it probably should be the actual fighting weight. I would certainly reweigh any bot which added a major component in their repairs, but I'm not sure I would bother reweighing a bot which lost a piece. Jboyd, care to weigh in?
2. There is no clear limit on what you can do with the tools you impounded (although SOINC has screwed that sensible limitation up now), but the bot would still have to be legal at the start of every match.
3. Yes.
4. No.
5. Probably not, though.








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[JBoyd-NY]

1. When I do impound, the teams are told they have to mass EVERYTHING that they might have on their bot (for example, I've had teams bring weights to add to their bot to make it heavier for some bouts and and remove to make it lighter and faster for others. They have to mass their bot at impound with all the weights, so I can be sure that they can't exceed the maximum mass for the bot, even if they use all of the weights they brought). If a team subtracts mass from their bot and the bout ends in a draw, they should ask the Event Supervisor to re-mass their bot. I have no problem doing that, but it is the team's responsibility to ask for the re-massing, as things are much too hectic during the tournament to keep track of which teams have removed items from their bot.

2. As stated above, if you have additional features that you want to have on your bot for some bouts but not others, then you need to include those items when you mass your bot at impound.

3. I've said all along that a team with a so-so bot that has practiced until they are experts at driving the bot will beat a great bot driven by teams that have little driving practice every time. I, too, have seen teams that blindly play chicken with their opponents and then simply stand there trying to push their opponent while they are relentlessly pushed out of the ring. When I make presentations on Sumo Bots, one of the things I emphasize is that the worst possible strategy you can use is to attack your opponent head on, as you have no way of knowing at the start of the match whether your bot is stronger than your opponents, and in 95% of the bouts I've watched where both teams use this strategy, by the time the team with the weaker bot figures out that they made a mistake its too late to stop the opponent.

4. Byes don't count as wins in double-elimination tournaments. This is clearly stated in rule 3.c

5. The design mentioned sounds interesting and innovative and I'd love to see the bot operate. One word of caution - the bot is not allowed to exceed 40 cm x 40 cm x 40 cm at any time during the bout. If a bot has parts that move (besides the wheels/tracks) the team should be made to operate these parts through their full range of motion while they are in the 40 x 40 x 40 box at impound. Any feature that cannot operate through its full range of motion while inside the box would have to be disconnected during the tournament.

[ichaelm]

The rules are vague about rechecking the construction specs after a bot has been modified. I think it is implied that it is up to the judges ruling when to remass or remeasure a bot. Obviously a team cannot be allowed to add anything to their bot without having it weighed afterwards. JBoyd's system makes sense.

I really like the spatula idea! I wonder though, what about the spatula made it get under other bots so often? Was it just closer to the ground than most scoops, or did it seem to have something to do with the force of the impact?

[lakeside]

I really like the spatula idea! I wonder though, what about the spatula made it get under other bots so often? Was it just closer to the ground than most scoops, or did it seem to have something to do with the force of the impact?

More to do with the force, I think, since on most the robots the wedges were all about as close to the ground as you could get. Just that extra KE from going faster and probably weighing a little more too.

When I make presentations on Sumo Bots, one of the things I emphasize is that the worst possible strategy you can use is to attack your opponent head on, as you have no way of knowing at the start of the match whether your bot is stronger than your opponents, and in 95% of the bouts I've watched where both teams use this strategy, by the time the team with the weaker bot figures out that they made a mistake its too late to stop the opponent.

I agree completely.

The design mentioned sounds interesting and innovative and I'd love to see the bot operate. One word of caution - the bot is not allowed to exceed 40 cm x 40 cm x 40 cm at any time during the bout. If a bot has parts that move (besides the wheels/tracks) the team should be made to operate these parts through their full range of motion while they are in the 40 x 40 x 40 box at impound. Any feature that cannot operate through its full range of motion while inside the box would have to be disconnected during the tournament.

Yep, it was close to the 40cm mark but not over it, the supervisor specifically measured it after the match, which was good. I meant to get some video but I was too busy trying to figure out how I could beat it! Next tournament, hopefully.