DEWBOT VI Tactical

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Our basic strategy is to score goals and avoid penalties. We thought from the start that the extra point for hanging wasn't worth it, and despite experience at the Finger Lakes Regional we stand by this decision. The extra weight, complexity, height (few robots who can hang can also tunnel) and the possibility of the rack being full or being blocked by an alliance member wasn't and isn't worth the effort.

Complex Driver Control Documentation

Sab-BOT-age Strategy

Original Theory

Our basic strategy is to score goals. We thought from the start that the extra point for hanging wasn't worth it. In that 20 second period we can in theory score three goals. The extra weight, complexity, and the possibility of the rack being full or being blocked by an alliance member wasn't worth the effort.

FLR Experience

We never scored three balls in that time, in fact we only scored two the entire competition. Matches do often come down to those hanging points, though very few robots do so successfully (in fact most made our initial decision). The complexity issue still applies, and even with this information originally, we probably wouldn't have gone for it. There are also very few robots that can both hang and go under the tunnel, and tunneling has been rather useful for us. In fact, we were the first robot to go through the tunnel at FLR.

Philadelphia Experience

While we usually don't quite score 2 balls in those last 20 seconds, even if we had an average hanging device we'd almost always be better off scoring until the end.

Near Zone

Kick the original ball into the goal during autonomous. If we don't, ignore it when we begin teleop and get the other alliance's balls away from them and score as many of these as possible. Then sweep balls received the mid- and far zones into the goals. Consider moving to mid-field if something goes wrong with our mid-field alliance member and we run out of balls. Score throughout the finale.

Original Theory

Stay in the space, move all the balls into the goal. In theory, we have accurate short range kicking skills and the ability to herd (not possess) three balls into the goal. We think in most cases the opposing robot will try to hang, so we will have the space to ourselves. In the case where they do stay we can move around them.

FLR Experience

We didn't score a single goal by kicking, and only two by herding--both just one at a time, despite having three balls in front of us at one point. Most opposing robots did not try to hang, and several played effective defense on us, despite what should be our superior maneuverability and pushing power. If we started here, we usually didn't change zones.

Philadelphia Experience

  • Autonomous into Teleop: We usually kick the original ball during autonomous, but not into the goal. If the opposing robot doesn't clear it's balls during autonomous and is otherwise ok at clearing (i.e. it's not broken and can sometimes kick over the bump), out first priority in teleop should usually be to gain control of their balls. This is because the ball we kicked is much farther from them than their originals, so it's more useful to zoom over and steal theirs than work on getting ours in and lose the other 1-3. If the opposing robot does clear their balls, our first order of business is to score our original.
  • Teleop Strategy: Then we score all the balls our mid-field (or far, as the case may be) alliance partner gives us. Especially if we have a good defender on us, we should snatch up and possess any (one) ball that comes close while we attempt to outmaneuver them. This is because it's easier to outmaneuver them in front of the goal for the half-second it takes to kick than the several it can take to shake them, find and possess a ball, get to the goal, aim, and kick. We may lose the ball in the maneuvering process (though this is actually not overly likely since we can hold on to them pretty well with strafing and backwards movement), but we're more likely to hold onto it if we try than if we don't snag it in the first place.
  • Switching Zones: Sometimes, we a good mid-field clearer, we can do this for the whole match. If the ball tide does stem, we can switch zones and start clearing from the middle. Depending on our aim and whether the other alliance bot moves forward, we may end up clearing into the mid-field and then crossing to score in the near zone. We're also happy to pick off defenders so a high-scoring alliance robot can score freely, though there usually isn't another alliance robot in that zone unless it's near the end and we've hoarded all the balls (robot from mid-field) or if the opposing alliance is having trouble scoring on its own in the far zone (robot from far zone).
  • Blind Spot: Because of the blind spot right under the driver's station, if we run out of balls (before we switch zones) it can be helpful to sweep along the wall and maneuver any balls hiding there into the open. The coach/operator (or driver, though they tend to be busy) can usually see this by simply leaning over.
  • Kick Timing: In general, we subscribe to the 'when in doubt, kick' method (also when not in doubt), since the ball usually gets back to us if we miss. It doesn't always, though, so this is a judgment call on the drivers/coach. We've given the kicking function to the chassis driver because they usually know when they're best aligned. In reality, the method is more, 'when in doubt, be more likely to kick than doubt would regularly dictate, but make the probability difference proportional to the likelihood of getting the ball back. In scoring, the likelihood is inversely proportional to your alignment with the goal (walls are really good at making balls fly backwards). In clearing, the likelihood is inversely proportional to your perpendicular distance from the bump and skew angle, up to the point roughly just short of the middle of the zone when you're less likely to strike the 45-degree side at a low angle of attack such that the ball goes straight up, and/or from the less-than 45-degree skew angle such that a attempt would probably kick it out of the arena. In all cases, the likelihood drops dramatically if you're facing a guardrail--don't kick out of the arena.' Unfortunately, that would take most of the match to say.

Mid-field

Kick the original two balls into the goal (or at least near zone) during autonomous. If we don't, ignore them when we begin teleop and get the other alliance's balls away from them and score or move all four into the near zone. Then concentrate on gaining control of the balls from both returns and score or move them. Consider moving into the near zone if something goes wrong with our near zone alliance partner and we need to score. Consider moving into the near zone during the finale, coordinating with our alliance to avoid any hanging robots.

Original Theory

Stay in the space. Move by herding balls to one side of the field, shooting when possible. During the finale, stay to one side and shoot into the goal. While staying to one side lets the robots in the far zone have clear shots on their side.

Since mid-field is where the ball drops we will push the ones we can't score through the tunnel to the near zone. This will give our alliance partner more balls to work with.

FLR Experience

We did manage to shoot a several balls over the bump, though none got into the goal. We rarely herded through the tunnel (made difficult in part by lack of a usable snake mode). We usually didn't stay to one side during the end game, taking any shot we could. Most teams used this tactic, and we rarely got in each others way (in part because of difficulties kicking for both parties). We weren't shy about moving zones, and were happy to incorporate it into alliance strategy.

Philadelphia Experience

  • Autonomous to Teleop: Much like the near zone, if the opposing robot doesn't clear its 2 balls during autonomous, we need to judge whether to zip over and take them during teleop or clear ours first (usually the former, unless the autonomous kicks really change ball position).
  • Teleop Strategy: It's usually not worth it to herd through the tunnel, and we often more forward near the end game to score a few more into the goals (depend on the alliance robot in that zone). We're also happy to pick off defenders so an alliance robot can clear balls forward, though there's usually only another alliance robot in that zone when the opposing alliance is having trouble scoring on its own in the far zone. We'll take whatever shot we can get, though we do try to pay attention to anyone shooting over our heads.
  • Switching Zones: We're not at all shy about switching zones and always offer it during strategy (though it's not always needed). We can clear virtually all the balls we can see into the near zone, though not many make it in the goal.
  • Blind Spot: When offensively clearing, because of the blind spot past the bump, when moving from point A along the bump to point B in the open, we should try to move along the bump for as long as time allows in order to gain possession of any potentially hidden ball or push into the open where we can see it. It's not uncommon for alliances to be short points because they don't realize there's a ball just over the bump. This won't always work, but it's more likely to do so if you try than if you don't, and matches often come down to the one or two points we can gain from this.
  • Clearing the Bump: We have some trouble kicking over the bump when very close to it; this is mostly a vision problem rather than a kicking kinematics issue. Thus if we think there's a ball in the blind spot, it can help to turn on the possessor, run up against the bump, and then back up, bringing the ball to where we can see and accurately kick it. While we originally thought that early kicks against the bump weren't a major problem (the ball would come back to us), this isn't entirely correct as sometimes the ball will hit the bump and go flying backwards, at best making it difficult to recover and at worst giving it to the opposing alliance.

Far Zone

Kick the original three balls into the goal or mid- or near zones during autonomous. If we don't, either kick them out in teleop or try to block the other alliance's first shot. Then concentrate on playing defense and moving balls out of the zone. Consider moving into the mid- or near zone if we need to score, or if there's no major need to play defense (this is usually a strategic alliance decision). Get out of the zone for the finale, either into the mid- or near zone.

Original Theory

Stay in the space, score as many points as possible. At the end game move through the tunnel to the mid-field to give us a better chance to score. We will take balls with us to the mid-field area, we are planning to take the tunnel out, but can climb the bump if needed. If the opposing alliance needs to take the tunnel we will block it for a few seconds to slow them down then continue through.

FLR Experience

We didn't score at all from the far zone, and moved fewer balls from this zone than mid-field. We do play pretty good defense from here, but we aren't shy about changing zones, often incorporating it into alliance strategy with decent success.

Philadelphia Experience

  • Autonomous to Teleop: In general, we're better off clearing our 3 balls at the start of teleop than snatching theirs (though hopefully ours are already clear). This can change depending on the scoring capabilities of that robot and where the balls their alliance kicked in end up. This is more a clear-as-much-as-possible strategy than determining specific balls to go after. We should be flexible and not get stuck on one ball (this is true in all zones).
  • Teleop Strategy: We have a very successful triple-threat defense from this zone. We can outmaneuver virtually everyone, though sometimes they can score a little because instead of getting between them and the goal, we only pin them to one side/corner. We can also out-push most everyone, though not always completely and we do tend to lose the thread on them if we're not persistent. We can also clear most of the balls from this zone, though there's always room for improvement in the practicing the balance between clearing and pushing/blocking.
  • Switching Zones: If it becomes obvious that we don't need to play defense against the opposing alliance and we've cleared all the balls, we can move into them mid-field and kick into the near zone/goal and/or pick off the mid-field defender to allow our alliance robot to do the same. There's rarely cause to move into the near zone (though it never hurts to leave options open).
  • Blind Spot/Clearing the Bump: Much like the mid-field, we should try to move along the bump for as long as possible and/or run up to the bump with the possessor on in order to possess/sweep any potential ball to where we can see it.



DEWBOT VI Competition Team information has what the team is working on.