Each year I am amazed by what teams come up with to compete in FRC. Teams have a ton of wonderful ideas and some even see good execution of those ideas.
I would like this thread to focus on the “Minimum Competitive Concept” for a robot for 2013. It is often easy to identify all the possible tasks you could have a robot do. Prioritizing those tasks, and realizing it in the form of a competitive robot is in my opinion much more impressive.
Assumptions are that one of the priamry goals of the MCC is to play in elims (not necessarily win on Einstein), and you team has mid-pack to lower fabrication resources.
Please list your assumptions, strategy to seed high, estimate of a winning score, and what robot design elements would achieve this score.
This is always easier to do in hindsight, but here goes my MCC for the 2013 season…
Drivetrain-Simple tank drive, 4wd or 6wd depending on if the team were to go long or wide.
Shooter-Fixed angle straight shooter. This type of shooter is easier to machine, and can be made in a matter of hours. To change height of shot, the team simply changes rpm of wheel. The shooter needs to be low so it can be fed from the bottom slot.
Hanging. Passive climber much like 2338 had (we articulated ours up and down so we could go under the pyramid, but the idea is much the same). No motors required. Guaranteed hang every time.
MCC 2013 - Fixed angle shooter (bucket loader). Drops 2 into high in auton. (50% accuracy). Runs 3-4 cycles of human load. Pneumatic 10 point hang.
I would assert this robot, if driven properly, would be in contention at most regionals. Furthermore, I would also assert that the KoP drivetrain, FRC3313, and Ri3D gave every team the info needed to build this robot.
Even at 50% accuracy: 34 points isn’t bad (assuming hang)
I am torn over whether limboing should be in this list. It is not necessary to be be competitive if you are good at everything else you do, and makes hanging harder, but it is fairly easy to accomplish and really makes you better at defense, as well as beating defense. So, I am going to have to say yea for now
This year’s “minimum” is way higher than previous years due to the relatively easy game task. I would say the “minimum” robot would be a fixed, simple human loaded bucket shooter (linear, curved, does it even matter?) that could auton, cycle three times, and hang (passively is probably best for MCC). 2 point or 3 point goal isn’t that important but I don’t see many teams having trouble over six weeks tuning their robot to be accurate enough to use the 3 point goal.
This concept (the “pure cycler” distilled into its simplest form) is potentially competitive at all levels of play, falling off only at the Championship level, but then you can add a net and still be in the hunt.
Basic: Plywood circle-shooter with a ram-style hang. Feeds from chute over the shooter into a plastic-bucket-hopper, into a 90-ish-degree 8" treaded shooter. Shoots from either rear corner of the pyramid.
KOP Drivetrain that uses 2 CIMs total. Add more depending on available budget.
Shooter: Plywood wheel with the 3M friction tape purchased with PDV from AM, directly-driven by a CIM. Shooter channel uses 1/4" thick x 1" wide strips of squishy silicone rubber on the outside to provide friction for spin and plenty of cushion while the disc is under compression. Shooter is adjustable while in the pits (thinking 3/8" all-thread) so the exact angle can be tweaked, but is static while the robot is live.
Hopper: 5-gallon bucket, one with a very rigid rim support trellis on the outside (useful for mounting)
Indexer: Any number of motor/gearbox combinations would work here. Banebots RS-775 + 10:1 Versaplanetary would be my choice in order to spread the PDV’s around. The dual spiral arm would be made out of wood and would kick the bottom-most disc in the hopper into the wheel. Code would tweak the % power sent.
Feeder chute: Tough call for what material – need it to be smooth (various woods would work) but also be able to absorb some amount of energy from a falling disc (polycarb with some flex). Access to a heat gun & patience would make polycarb win. Just make sure the bottom isn’t concave. Mounted on top of the shooter, it has a fixed angle with the correct height for the middle feeder chute. Is doable in such a way that the robot can still go under the pyramid (useful for avoiding defense).
Hanging: ram-style hanger. I didn’t do this one during the season, but saw plenty of robots do it right and plenty do it wrong.
Bumpers: (yea, that’s right!) Letters are all-white and are spaced according to various calibration points for lining up shots. That way the driver knows the range of depth where a shot will hit vs miss. Simply put the pyramid corner on one of the numbers.
4-5 cycles, 18-point autonomous, 10-point hang. With practice, could lead an alliance into elims. Without practice, the team would easily make a great off-side cycler.
IMO, the problem with using the de-facto defense box-on-wheels-with-pool-noodles robot is there are plenty of alliances with FCS’s that would not what that type of robot unless the robot was GREAT at pushing others out of the way. That means 148lbs, (probably) 2-speeds, and an extension for the FCS blockers such that they can be out of the way. This adds pneumatics, which an MCC team (IMO) probably wouldn’t understand well enough to maintain over the course of a season.
IMO, a 4 CIM minimum drivetrain is a must, especially for a MCC. When my team is looking for a second round pick, this $60 choice would be the difference of them making the eliminations, and packing up early.
This is an interesting year for an MCC, especially with how the game played out. In this case and MCC could actually be a very very competitive machine at the majority (if not all) levels of competition.
It’s almost an 1114 (minus climber) / 862 hybrid (lite) machine.
KOP drive - Wide configuration.
Single Speed 4 or 6 wheel drive. 4 CIM Toughbox/Mini-Toughbox transmissions.
Passive 10pt hanger.
Human player loaded - Front loaded (similar to 1114).
Roller fed, single wheel 1/4 arc shooter powered by a CIM/Mini-CIM.
2pt, maybe 3pt goal capability.
No speed control, just % based shooter control.
Almost any team could build this machine…and it would be incredibly effective as a secondary scorer or, for sure, a third machine. It seems odd that an MCC could actually be this simple, yet this effective.
And with a couple of more advanced tricks, such as a non-passive hanger to be able to get under the tower and a higher level drivetrain (shifter or 6 CIM single speed) and you have a World Championship level machine with a great driver (*610 anyone?).
*As a side note, I have not actually seen 610’s machine, but I imagine it’s simplicity is what made it very effective.
I kinda wish I had this perpective at the start of the year. Would have led to so much less burn-out.
Building off of what Nemo said, a lot of your MCC concepts seem much more like early 1st round selections and alliance captains. 18 point autonomous modes? Three, four, FIVE(!?!) cycles?
Until week 5, the mean elimination score for each week was beneath 100 (with it basically sitting around 80 points until week 4). Week 5 and 6 was right around 100. The median elimination score for the year was substantially beneath 100. The goal isn’t to win a regional, but simply play in the eliminations.
A robot that can contribute in the low-mid 20s offensively (ie, autonomous and 10pt hang) and a bit of defense is more than adequate to reach the eliminations at a majority of events.
MCC is a great road-map for many 2nd tier teams. We are definitely a 2nd tier team in Texas and found success with a MCC robot.
zero machine shop time (hand tools only) , no welding
occasional laser cutting (varies on donations and friends )
partial field to practice (no pyramid)
shoot 3 point shot from one place (use physical hardstop to align)
passive climb (no actuation , can’t build a pyramid , so climbing is out)
passive feeding of frisbees
be tall enough to not be blocked
Though true, shooting this year was really easy. 2169 doesn’t get much simpler. Yes they were super competitive and Galileo finalists. But their robot was a 1 wheeled curved shooter and a 10 point hang. They made 0-2(if blocked, though very rare) runs per match and scored 3 discs in auto.
The MCC, almost any form discussed here, this year could have won Einstein.
I think this comes from a mild discrepancy in what MCC is intended to mean. Many people are taking it as ‘what shouldn’t be that hard’, while others are following the OP’s ‘how to play Saturday afternoon’. I think it’s uncommon for the former to end up so much less than the latter (very cool game!), so it hasn’t come up much in the past.
I’d say to play Saturday afternoon, the bare minimum you can do is put the kitbot on steroids together, put a solid but light (low CG) blocker+passive hang on it, and buy an extra set of wheels. Then proceed to drive the original wheels off for the remaining 5 weeks. Know the rules really, really well. You’ll hear your name before lunch Saturday at nearly every qualifying event. (Don’t have a practice field? Find a parking lot–that’s what the extra $40 in wheels is for.)
The next step up from this is to mount a low autonomous-only shooter in front of the blocker+hanger. Do the math: don’t move to 3 discs or the high goal if it lowers accuracy too far. Work on human feedings if there’s time, but don’t sacrifice drive time for it (if the goal is to play Saturday afternoon).