MCC (Minimum competitive Concept 2015

[IKE]

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.

[AllenGregoryIV]

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.



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.

[Kevin Leonard]

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.

[GreyingJay]

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.

[GeeTwo]

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.

[GeeTwo]

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.

[Allison K]

Originally Posted by GeeTwo

...

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.

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.

[IKE]

Originally Posted by GeeTwo

3946's robot this year was of an MCC type. ...snip... Our goal was to be selected by presenting some distinctive capabilities that would appeal to a high seeded alliance. ...snip...

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.

[GeeTwo]

Originally Posted by IKE

I understand why you might believe this to be the type of concept I am looking for, but to me it is not.

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.

[GKrotkov]

Originally Posted by IKE

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.

Would you consider specializing to make sure you get into eliminations by being the first pick of the second round (rather than dead last) fulfilling the "play in eliminations" requirement? Or do you really need to be gone by the end of the first go-through?

For example, in last year's thread, the general consensus pointed toward an inbounder/assist bot, which, in many cases, would not be picked in the first round.

[EricH]

I can think of a robot class that would qualify. Team 4 is one example; Livewire is another (sorry, forgot the number). There are others.

Drivebase as a fairly standard tank drive. Pickup is a series of hooks for the totes mounted to a chain or belt going up a tower. Maybe a specialized hook for a can goes on the top. If working the chute, a ramp-on-tether gets added.

And of the 3 of that type I can think of off the top of my head, I can remember 2 making elims and I'm not sure about the third.

[echin]

Originally Posted by EricH

Pickup is a series of hooks for the totes mounted to a chain or belt going up a tower.

1519 is an example of this, though they had a can claw and can grabbing arms. They were the first seed and winners of all three district events they went to as well as the NE district championship and had an incredibly consistent 3 tote auto.

[Gregor]

Of highly competitive simple robots, only 1325 comes to mind.

Entire robot was literally 'elevator goes up, elevator goes down, drive.' Passive 2 stack ramp and passive elevator clamps lead to 3 consistent capped and noodled stacks a match.

Originally Posted by echin

1519 is an example of this, though they had a can claw and can grabbing arms. They were the first seed and winners of all three district events they went to as well as the NE district championship and had an incredibly consistent 3 tote auto.

1519 was incredible, but they're not even close to an MCC.

[echin]

Originally Posted by Gregor

1519 was incredible, but they're not even close to an MCC.

True. They are an example of the concept I was reffering to though, just extremely well executed and thought out.

[Woolly]

Assumptions:

• For an MCC, seeding high isn't a concern.
• Coop isn't going to get you picked for eliminations.
• Looking at the regional events we attended (Greater Kansas City, Oklahoma), to be in the top 24, your robot needs to average more than 18 points per match. So that's 9 totes or more on the scoring platform, or a stack of 3 with a can on it.

Woolly's MCC#1: In Memory of Dozer
Goal: Average 9+ totes.
This design relies primarily on a competent driver, and a decent drive-train, and not much else. The chassis has a wedge on the front to be able to break up the landfill so that the totes can be pushed onto the scoring platform easily.
Drivetrain: AM14U2 Tank drive, 2 CIM
Positives: Simple, easy to improve, works well with other landfill bots as breaking up the landfill usually improves their output, easy to improve.
Negatives: Relies heavily on the driver, Makes a mess on the field potentially slowing alliance partners trying to pick up cans or do Co-op, takes up a lot of space on the scoring platform.
Potential Improvements: replace wedge with roller intake (may even be able to be based on 2014 designs), can-burglars.

Woolly's MCC#2: Diddy Kong
Goal: Average 1 stack of 4 with a bin on top
Imagine 4522's robot. Now remove the seat belt. Replace the H-drive with an AM14U2. Remove the can burglars. Give the drivers less practice time due to the MCC building team having less resources to be able to get it done in decent time. Also make the controls a lot more convoluted for similar reasons.
Something similar could be accomplished with having the ramp not built into the robot, and that would make it more advantageous to add a powered intake at a later date.
Drivetrain: AM14U2 Tank drive, 2 CIM
Postives: Better learning experience than MCC#1, relatively easy to make into a regional winning robot, shouldn't disturb alliance partners.
Negatives: Still pretty complex, requires good communication between driver 1 and 2, requires much better programmers than MCC#1, may be less consistent due to complexity and cans rolling off the stack.
Potential Improvements: See 4522's robot. Also, powered intake.