MCC (Minimum competitive Concept 2015

#1

Previous years are located here.

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 2015. 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.

If you haven’t watched the Simbotics Strategy Presentation, please do before responding to this thread. Especially review the “Golden Rules 1&2”.

Assumptions are that **one of the primary goals **of the MCC is **to play in elims **(not necessarily win on Einstein), and your 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.

I personally usually assume for this thread that the goal is to seed high enough to be either a Alliance Captain or a pretty early pick. I would appreciate this year if we kept towards that philosophy as opposed to getting into a KOP Robot/Cheesecaking discussion. Not that it isn’t a viable concept, but I think it has been covered at length elsewhere.

[MCC] Minimum Competitive Concept 2019
#2

I’m going to throw out our 8ish hour robot build as the MCC. For those of you that don’t know, we completely tore down the robot to its two drive rails and built a new one at the Arkansas regional.

We made playoffs at all three of our events, including champs, as the third robot on the alliance.

Most everything could be made from Versaframe if you wanted, and a whole lot of #35 chain.

http://www.chiefdelphi.com/media/img/b2a/b2a5e4b2a80df65b97229ff9bce51b5f_m.jpg

By champs we could do stacks with cans on top and if you just wanted stacks of totes we could do that all day.

It only weighed 100lbs so it was great for cheese caking which was pretty important for a lot of robots this year at events.

#3

A few robots come to mind this year as MCC’s.
1711 was the third robot on the MSC championship Alliance, and the fourth robot on our Carson Championship Alliance. They could make stacks of 4, cap stacks of 4, and grab cans. Very simple robot as well.

558, as usual, came up with an effective and simple design utilizing mostly COTS materials. They were the third robot on the 1730 Alliance in Carson this year, and primarily advertised themselves as a capper of stacks of 5. They also had can grabbers.

263 won South Florida early on consistently making 1 stack/match, then attended two New York events, where they upped their game to 2.5 stacks/match. Their robot consistently of a short elevator with Indiana tabs on one side and a short elevator to grabs cans with on the other.

Lastly, the simple concept of the year, 1325. 1325 captained the #2 Alliance on Carson to an Einstein berth using a design simpler than almost any other effective design in the world. 3 stacks/match from the feeder with only two motorized subsystems on their robot.

EDIT: One more that I forgot was 4967. 4967 is from Michigan, and consists literally of just an elevator with a hook on it that they used to mine the landfill and grab RC’s from the step during teleop.
They were a high seed at multiple events, including MICMP, where they captained the 11th seeded alliance to a semifinal berth.

#4

I think this year what it all boiled down to was consistency. If you built a robot that could do something (like stack totes) and do it every time, you did well. As a byproduct you were also very predictable, which made it easier to be an alliance pick.

Like Karthik said in his presentation, initially it looked like this game would be perfect for specializations - landfill stackers, feeder stackers, and cappers. However it seems that in the end, the robots that did the best were those that didn’t rely on other alliance members for help. I think this is because in the end most robots were not super consistent. A stacking robot that relied on the performance of another capping robot to succeed (and vice versa) would drop in the rankings as soon as one or the other robot made a mistake, but an all-in-one robot that could hold its own ground, kept going. Some specialists did make it through. The ones that succeeded were those that consistently, time after time, did what they were designed to do.

Initially we designed our robot to be a fast landfill stacker. That did not work as well as we’d hoped (mostly because we ran out of build time). By the end of the season we had evolved into an all-in-one that could do coopertition and then make our own 4-tote capped stacks. 40-80 points per round. Nowhere near the best robots, but we were finally consistent.

Had we gone into our week 3 regional with what we had at worlds, we would have done much better. Of course any and every robot improved over time. Which again says to me that winning is about being consistent. Part of that is engineering away your mechanical failures and flakiness, and part of that is confidence and practice on the drive team.

Also, part of our day 1 strategy was to be good at coopertition. This is the one thing we did well every time (notwithstanding elevator/clip failures), because it was an easy 40 points. This was perhaps short sighted given that after qualifications were done we had little to offer to alliances.

#5

3946’s robot this year was of an MCC type. For most of our matches, we had 3 CIM motors and no other actuators, and all of the sensory feedback was through the driver. With this, we played in (regional) elims as part of the champion alliance. Our goal was to be selected by presenting some distinctive capabilities that would appeal to a high seeded alliance. The first non-obvious strategic decision was to play the landfill and step. This is why we did not have forks or a body that wraps around the totes - we went for a relatively flat front face that could get right next to a tote even if it were packed in the landfill or atop the step. We had a 4 wheel omni tank drive and a single lift stabilized by dual chains and a relatively flat face that could grab tots and RCs by the lips on the edge, or the RC handle. Our only really innovative solution (that worked) was our “rake” which features 20 10-32x3" steel machine screws which are spring-mounted in a piece of 1.25" c-channel to allow greater flexibility in grabbing game pieces. This rake proved to be as much of a liability as an asset, as we never did learn to make well-nested stacks consistently, limiting us to carrying two or at most three game pieces per trip. We were selected by the #2 alliance at Bayou because of our ability to mine the landfill, including flipping the totes next to the step, and then to remove RCs from the step for scoring. In the canburglar-poor environment of Bayou, it was good enough to be able to get an RC in 60 seconds.

We installed a variety of sensors throughout the build season, but between poor sensor mounts and a mostly-rookie programming team, we never did get any of the sensors working to line up the robot with the RCs and totes well enough to help our scoring ability.

At CMP, we figured that the top alliances would become starved not only of RCs, but of rightside up totes. Our ability to flip totes and to remove them from the step would have been valuable had this been the case, but no alliance was able to score all of the “easy” gray totes and need more.

#6

Minimum competitive concept for 2015 - reliable can burglar. Note I didn’t say fast, I said reliable. At most events (at least in NE) this would have been a first round pick due to not wanting to deal with playing at a disadvantage with cans.[1] Now, likely this would not have resulted in playing very deep into eliminations. But, if my math is right being picked twice in the first round and making QFs would likely get you to DCMP.

What would this involve? A flow controlled cylinder and some either fiberglass rod or pvc. Oh, and the KoP drivetrain. Which, even accounting for my constant pessimism about the abilities of teams, makes this the cheapest to implement MCC I’ve ever come up with[2]

[1] There’s a discussion to be had as to whether this was a rational decision, I’d make the argument that most teams picking can burglars first round were being irrational as the majority of alliances at district or even NE DCMP were NOT constrained by cans. BUT the fact remains that these picks were consistently made through the first 5 weeks.

[2] I don’t think I did one for 2010, which would have been cheaper as I would have said “a drivetrain that doesn’t involve those AM lift kits and drive practice”

#7

I know you added the qualifier about NE events but at both NC and Palmetto… those machines would have been lucky to have been picked at all. I suspect there were events elsewhere that were similar. That might have more than a little to do with the region mind you…

At any rate, I would agree that a reliable mechanism is always better than a purely fast mechanism. Combining the two is deadly.

#8

The slight issue with this argument is at weak events, no one would pick canburglars.

#9

In order to meet the “top 12” criteria o being either an alliance captain or a likely early pick, the goal even at CMP was essentially that you could put up two tall (5 or 6) capped stacks fairly consistently. There were a number of HP-feeding stackers that met this goal without being unduly complex. Many had tethered or internal ramps that passively caused the totes to automatically fall into the same location and orientation relative to the robot every time, simplifying the stacking process. Quite a few used the same lift mechanism designed for totes to also acquire and pre-stack RCs. Some were entirely modular (e.g. versaframe) and COTS (e.g. KoP, AM/vex gearboxes, COTS wheels) construction.

Another MCC concept that we considered and would have worked well but I do not recall seeing very often was the “RC specialist”. This would have required a decent canburglar that could work both in auto or teleop, and the ability to cap tall stacks placed by your alliance partners. There were a number of teams which would have scored an additional tall stack of totes if they did not have to round up RCs, and the RC specialist would have been a fruitful addition to such an alliance.

#10

I understand why you might believe this to be the type of concept I am looking for, but to me it is not. I am looking for simple that can qualify high, or be an early pick. Hoping to be the 3rd member of a #1-2 alliance I have found puts you in a high probablility of not being picked at all which defeats my playing in Elims requirement.

This does not mean that picking this sort of strategy is a poor strategy for a team to do, just not the intent of this thread. The strategy your team executed can be a very good one for being part of the winning alliance or making it to worlds. It just also has a nearly equal probability of sitting out Saturday afternoon.

#11

That’s what I’d assume too. I’d claim NE is pretty weak and yet I consistently saw can burglars going really early at our events. Why? I have no idea. As I mentioned, I feel this was an irrational decision and I have no evidence more detailed than my anecdotal experience. Maybe it was a solely NE centric bout of insanity. Or it might have had something to do with depth of events. Not really sure.

#12

Did you guys actually see reliable ones that did not get picked up? I am not disagreeing with that statement, but thinking back, I cannot think of any reliable ones that did not get picked up at Michigan districts. To be fair though, there was a ton less of these than I expected.

#13

Absolutely. between the limited role of defense and with advancement based on “points” rather than “victories”, consistency was king no matter what tasks you were doing.

#14

We were the RC specialist. We got ourselves into a bit of a pickle and (with some guidance from outside sources) decided to go this route instead, after it became obvious in week 3 that our original strategy was not going to pan out within the time remaining.

We weren’t the fastest burglar out there by any means, but we were fairly consistent with the auto mode (we could do left two or right two), we could turn sideways cans to vertical (upside down was easier than rightside up, but we could do either), cap stacks up to five, and prepare noodled cans for us or our all-in-one specialist partners. We could also manage one gold tote efficiently in the pincher claw. Our most common match strategy was burgle the right two cans, stay out of the way of the stackers, put a gold tote on the step, noodle the staging zone cans, upright the burgled cans and get them out of the way, cap whatever stacks had been made by the time we did all those other things. It was enough to get us in elims at both districts and states, including 5th alliance captain at first district and as 1st pick by the 3rd seed at our second district.

Ours was probably fancier than it needed to be, but I feel like the mechanisms we actually ended up with (a four bar arm, a pincher claw, and a winch spool to retract the can burglar) should be within reach of most teams.

#15

My apologies; I originally read the last paragraph of OP to mean something entirely different. “I personally usually assume” to me implies that this is not necessarily an assumption here.

#16

At the regional level, I saw very few (if any) robots who had reliable Canburglars, but didn’t have other elimination worthy functions. Most teams that I saw who were picked for Canburgling, would have been picked otherwise for their stacking/capping abilities. As such it’s hard to evaluate the claim.

#17

New York Events had a few teams that were picked solely for their ability to grab cans from the step, whether that be autonomous or teleop. 4203, 174 come to mind. These were the last selections, however, at both events. All the alliances below #1 needed scoring robots for their third robot.

These robots also grabbed during teleop (which was fine for these events, no alliance was grabbing all four during autonomous, and only one or two alliances were capable of more than 4 fully capped stacks).

I also can’t think of a robot at either event capable of grabbing containers from the step that was NOT selected.

#18

I agree that a “pure” canburglar, with no scoring capability, would have been a long shot for both first and second picks at nearly any regional. Burgling a can without the ability to right it and deliver it exactly where the alliance needs would not meet MCC criteria. That said, even most of the **unreliable **burglars I saw picked or got picked - for scoring ability. Also, while the materials list for a canburglar is pretty simple, the tolerances for a mechanism that reaches across three rows of totes to retrieve, release, and (preferably) orient an RC are trickier than for a passable forklift, boat lift, or even side lift. That is, anyone who can build a can burglar is going to be able to put something else useful on the robot.

#19

I’d say a MCC at most regionals is a kit drive train, a simple lift (using REV extrusion, 80/20, or VersaFrame), and then lots of human player and drive practice.

Gets you 40 coop points (round it to 32 on average, say you missed a couple), and somewhere from 30-40+ noodle points (with proper strategy/good partners), and if you’re well practiced a few small stacks for 20 points or so.

That would rank you reasonably well at pretty much any regional outside the extremely competitive ones, and pretty much guarantee playing on Saturday afternoon in some capacity.

#20

1726 made a robot that was able to achieve the goals you stated for a MCC robot. We knew that cans were where the points are, and decided to make a robot that could deal with cans effectively, and also deal with totes less effectively. We figured most other teams would be making stackers that would work at the chute door (yes, chute door) so we decided to make our be able to get totes from the landfill for small stacks, and be able to cap other teams’ taller stacks. It worked pretty well, we were in eliminations in our regionals, although we ended being the highest ranked unpicked team in our division at Champs.

The big claw works well for grabbing cans, and can upright them with some practice. It can also grab a tote if needed. The small lower arm will lift a tote onto another, and can make a stack of two relatively easily, but a stack of 3 or 4 is pretty sketchy to move around without falling over.

Bonus points for the relatively low level of fabrication skills and materials needed? The judges at Alamo thought so. And it makes the game interesting to play, every match is different if you’re the capping robot