The missing feature: A common thread

FIRST General Forum
#39

I think you may have been generalizing a lot with the “Elite teams have parts made for them” statement, but I’d absolutely agree with you. Whether they make the part themselves via their own equipment, or have a sponsor machine the parts for them, good machining capability can be a staple of making a great robot. If nothing else, it opens doors to new possibilities.

This year, my team experimented with Swerve drive. We never would have been able to fully manufacture a prototype and competition bot without A) our CNC mill to make the modules, and B) one of our sponsors making us the frame. The machining was solid, the programming was a little sketchy, but overall, we had a style of drive train you don’t find on the ‘average’ team. Our machining capability played a huge part in that. And because of that, we can continue to improve it. Should the decision be reached to do so.

I agree, lets not turn this into an ethics of sponsor machining debate, but I have to agree that machining certainly helps. If you have access to CNC machines, laser cutters, water jets, etc. you’ll be able to manufacture components of a higher caliber which, in the end, can lend itself to a higher caliber robot. It’s not necessarily a direct correlation, but I certainly can’t deny that it helps.

#40

Hi-tech machining and fabrication is not the key; it’s the simple act of understanding your capabilities and resources that will separate the high level team from mid level.

A box on wheels with a solid bridge mechanism coupled with drivers with lots of stick time would almost certainly have been a picking team this year or very valuable team to a top alliance.

Also practice, practice, and practice. It’s an axiom that Paul Copioli shared with me during the Overdrive season; a team that builds two simple robots will almost always out perform the best complicated robot with drivers with little practice. We had a bot with lots of potential that year but it needed a lot of time to tune and develop it properly. It was also a little difficult to operate. If we would have had a practice bot that year we would have done much better. After that year we started building two bots and you can see the improvement in our performance.

Our drivers logged at least forty hours of stick time before their first regional and almost an equal amount before the second. Most drivers will never get more than a few hours of stick time every year. Our practice bot broke repeatedly but we learned from that and our comp bot never had a mechanical problem.

Also being flexible during the design process. Our shooter took almost five weeks to develop this year and many on our team wondered if it would even work. We were going out on a bit of a limb. We designed our robot to accept our fling-a-pult but also to use a conventional shooter just in case it didn’t work. I still have the parts for the conventional shooter sitting on my desk at the lab.

The last thing those elite teams have is institutional memory. For example teams that played Aim-High had a huge advantage this year. They didn’t have to develop the knowledge of picking up balls and moving balls through the robot, not as easy as it looks. They also have experimented and developed different drive systems and only need to adapt this knowledge to the new game.

#41

The majority of parts I end up making on our CNC could easily be made on a manual machine…if you were aiming only for functionality and didn’t care about making fancy parts. We machined at least 50 unique parts on our CNC this year from week 1 to week 6, but the vast majority were nice looking parts that could have been cut on a bandsaw and sanded to fit, or made on a manual machine. It’s a huge drain on time and resources to make parts like this, and it’s not like its impossible to hold a tolerance on a manual mill.

CNCs aren’t magic. Your parts aren’t going to be made to spec if you don’t know what you’re doing on the machine and it takes a fair amount of time for every unique piece. This may or may no seem obvious, but it seems like a lot of people are under the impression that a CNC is going to solve all your problems.

If you do have a CNC, chances are you’re not doing too badly. But that’s not because of the machine.

#42

I think many teams need to take the time to stop and look for weaknesses in their designs. Kinda related to Amdahl’s law, you want everything to work fast, without there being a bottleneck somewhere.

You could have a really fast and accurate shooter, but that’s no good if your ball-collecting mechanism is slow and clunky and can’t actually catch and send balls to the shooter fast enough. The shooter would be hindered by the collector, so trying to make the shooter even better wouldn’t do much good unless you improved the collector first.

The opposite also applies. You could have a great collector mechanism that quickly grabbed balls off the field, but that’s no good if the shooter takes a while to fire, or if it’s not very accurate. The collector would be stuck doing nothing waiting for the shooter to fire a ball, as you can only hold 3 balls at a time. If it missed, the robot would need to spend even more time recollecting more balls to shoot.

Basically, focus on making the weakest part of the robot better. Any team can do this. If you don’t, all the other parts of the robot won’t be able to perform at their best.

#43

I think I just need to clarify what I was saying.

I wasn’t implying that you need machines to do well, or that having simpler machines put you at a disadvantage (most of our best seasons came years before we had a CNC mill or a sponsor to do parts for us).

The point I was trying to get at is having specialized machinery speeds up the process at which special parts are made. Like it was said above, it takes longer to create these parts on a bandsaw or drill press and finish them to specification than through other methods. It’s also easier to get higher precision from using CNC equipment than a drill press or bandsaw. I know THAT from experience. Faster, more precise machining means the robot is ‘completed’ earlier, means more time to program and practice with a robot. Which leads to better performance.

Specialized machining methods do help. But it DOES NOT guarantee success. It’s merely an aid. In my opinion, a very useful aid.

#44

I must be on the wrong team then, because we have no automated fabrication capabilities. We do have a sponsor who cuts our 1/8" thick side plates to size for us (I lust after something that’ll cut thick aluminum better than our band saw) but that’s about it. Our machining capabilities consist of a wood band saw that we abuse by cutting metal with, 2 drill presses, a chop saw, and lots of hand tools. Oh, and a metal lathe, which we hardly use (because our designs generally don’t need that). Not even a bending brake. But that’s not why I posted this.

Don’t underestimate the value of collaboration with other teams. During the build season, we routinely visit other teams, sometimes in person and very frequently Virtually using Skype or Adobe Connect or something like that. Plus e-mail, lots of e-mail.

As an example, a bunch of us went to visit team 75 at the end of Week 1, where we saw a Bridge for the first time, as well as 75’s awesome mechanism for getting over that bridge. We stole that idea lock, stock and barrel and used it to our advantage. We gave back some advice on making their wooden bridge act more like a metal bridge, which they implemented, allowing them to have realistic behavior to work with.

We also got an idea for bumper mounting from another team, and explained our reasoning for going with a narrow bot instead of wide.

Last year, we had a local business give a class in Leadership to 4 teams’ student leadership. They learned what the job of a leader really is, and got some ideas on how to be better at it. I think all of us benefited from that.

This goes on year after year. It is a give and take, and everyone benefits. Plus, there’s Pizza!

#45

This. Although I wouldn’t count us in the top tier of teams, we’re definitely on our way there. A number of our design decisions this year were made based on successful designs of the past and knowledge of team history (particularly, designs we’ve done).

With regards to the difference between actual FRC robot design and real-world design, I couldn’t agree more with how useful familiarity with the FRC components is. When we went with mecanum drive last year, our electrical mentor (who we regard as a demigod) pushed us to use Jaguars, because he was confident that the Victor’s measly 120Hz refresh rate would hamper effective driving, but we ended up discovering that it was perfectly sufficient, and seeded higher at CMPs than we ever had before. It ended up that his familiarity with real-world applications, and unfamiliarity with FRC applications, while extraordinarily valuable, ended up backfiring on us and cost us valuable time in build season.

#46

I understand that there are certain features that powerhouse teams have that can set them apart from other teams, but i think there are a lot of power house teams that do not have the drop down collector. 1717, 148, 118, 399, 987 (Before this weekend), just to name a few, did not have this. I think the reason why a teams robot is “powerhouse” is because of how effective it is at the game. For example 16 did not have a fly wheel, they used a catapult, but because it was implemented correctly (effective), they were “powerhouse”. Though i understand your point about common design features that powerhouse teams have.

#47
#48

We are by no means a powerhouse team, but these are things we found out that help, and that a lot of powerhouse teams, and we feel can benefit all teams.

  1. The assumption that a CNC makes everything possible is false. I know for a fact that Team 4 Element has a CNC mill and lathe, and yet is not able to use them, because they lost their mentors who knew how to operate them. Furthermore, even 254 uses their regular lathes and mills often. If you read their build blogs, they do a lot of the machining work themselves. http://www.chiefdelphi.com/forums/showthread.php?t=95347

  2. Something that helped us do better this year, was pushing our motors to the limit. Instead of assuming a certain gear reduction was enough, for example we calculated how fast we wanted a ball to come up our elevator, figured out what gear reduction we wanted, and then figured out if we had enough torque. Do this with everything. DO THE MATH.

  3. Build to your teams capabilities. If you have a mill or lathe, then design your robot around those machining capabilities. Also, it is easy to get sponsors if you work at it. Most people would be surprised how easy it is to get a 2D sponsor, and they can really help speed up your build.

  4. Design within your teams capabilities. Using 254 as an example again, while many powerhouse teams decided to go with a turret, they instead went with a non moving shooter. Yet they made it effective, and I’m sure gained more practice time from that decision.

  5. Gain from the experience of powerhouse teams. Reading the build blogs of 254 and 148, and the New Cool really helped our team to improve. Paying attention to CD also helps. For example, we went into the season not really sure how to build an effective WCD. We searched CD for help, and eventually found 973’s CADs. They really helped us build a more effective WCD. Remember, innovations is made by copying and improving.

  6. Work with other teams. Both teams will gain. Right now we are developing a swerve with 1515, and it has helped so much. Really, you can see how much this works, with partnerships like 148 and 217. Also, CD is kind of like this. You can get help from other teams.

#49

For anyone who can’t make it to Karthik’s 105-minute “Strategy” presentation in St. Louis on Wednesday, I’ll go ahead and give you the first few lines in my notes from the last 2 years’ presentations (summarized):

  • His name is Karthik and his team wins alot. His teams proactively seeks to help other teams as well.
  • When determinining where time and resources are spent, there IS a priority order on every team regardless of whether that priority order is explicitly stated.
  • The #1 priority is the thing that MUST work every match to be able to do anything, and that is DRIVE TRAIN.
  • The #2 priority is the FIRST thing the game piece touches before it can be scored and that is the game pieces ACQUISITION MECHANISM.
  • Robot functions should work 100% and not be some over-constrained half-thought-out almalgamation of metal and motors.
  • This implies that if priorities are out of order, then the pickup function may suffer the most due to spatial and weight constraints.

Ergo, if the first thing a team designed on the robot this year was a shooting mechanism then there’s a good chance the intake mechanism was a secondary priority. That means there was less brainstorming time and more constraining factors given to that mechanism overall. I know that as Week 1 progressed, this is what wound up happening on my team.

#50

If you look at the original post, all the “missing features” related to game piece acquisition. Actually, that makes so much sense.

#51

While 95 is not really a power-house team, lately we’ve been coming up with pretty good mechanical designs I think. I.e. the double roller claw in 2011 and an over-the-bumper collector this year. What we ask ourselves is “what would make it easiest for the driver?” We knew that reorienting the tube for placement, and having the widest possible mechanism to pickup balls, would make the drivers’ life easier, so we implemented them. It’s the question that we ask ourselves that generally results in a good design I think.

We did not miss the ‘stinger’ balance assist mechanism idea, but we did undervalue its importance and therefore did not build it :frowning:

#52

Alas, if only our shooter had worked as well as our drive train and ball acquisition mechanism… :frowning:

#53

Your robot is only as good as it’s weakest piece.

Your team is only as good as it’s weakest resource (students, materials, tooling, mentors, time, money, space). Powerhouse teams are alike in that they have all managed to have enough of these resource. Stuggling teams are short some place but each team may have a different resource that they need to try to increase.

Teams that know that they have all the resources need to succeed, can work to build a robot that can do what is needed to win. Those that don’t focus on being able to show up.

Powerhouse teams aren’t powerhouse because they build great robots, they are powerhouses because they build great teams.

#54

Absolutely. This was a case of us thinking we could pull off something that ultimately we failed to pull off. On the bright side, we’re overjoyed with our drivetrain as a base for future robots – with some redesign and tweaking we think it will be applicable to almost any situation. :slight_smile:

#55

If you have a good general design approach for your chassis/drivetrains that can quickly be adapted to any game, that frees up a lot of time and brain power to focus on the “top end”. It also lets you start building shortly after kickoff, which spreads the fabrication schedule. Chassis/drivetrain prototypes are great pre-season projects. I doubt many powerhouse teams build a chassis/drivetrain that isn’t based on something they had previously worked with.

#56

As a senior on a five year old team, I can vouch that our “powerhouse” status (we aren’t, but bear with me) came when we a) started collaborating with the other powerhouse teams and b) started building two robots. We have been lucky to go to championships every year, and we went to IRI last year. The networking and collaboration with other teams has allowed us to use their ideas, and coop them for our robot.

So! As a member of a not-really-powerhouse team, if can build two robots, do it!

Also, try to move away from the kit gearboxes and frame. Doing that forces you to design what you want, rather than what you’re given. Big difference in attitude with that shift.

And if you guys need anything, just ask 2415!

#57

When I look at a robot, I divide the mechanisms into 3 categories. Drive-train/Grapples/Hangers/Ramp-wedges, devices which manipulate the entire robot. Conveyors/Lifts/Arms/Indexers, devices which manipulate the game piece indirectly, or when it is isolated from the field. Grippers/Intakes/Shooters/Ramp-arms, Devices which actively control the game pieces while in contact with the field, as well as portions of the field.

    High quality robots always have an excellent drive-train, usually a high traction skid steer drive.  I don't think many high rate teams work too much on a drive-train during the season, they build something similar to what they have done in the past, and make it as light as possible.  The drive-train is something that shouldn't take much time to do because it should always be an iteration of a previous robot.  Devices which manipulate the entire robot are typically focused on delivering as much power as possible, and being as sturdy as possible.

  Middle manipulators on high rate robots are usually simple and fast.  The primary design goal of the middle manipulator is to avoid hampering the ability of the end manipulator in any way.  The middle manipulator on most high rate robots avoids using available motors, power, weight, and time needed for the end manipulator without being sub par.

  The end manipulator/manipulators is what really sets the high performance robots apart from the average robots.  The end manipulators for both acquiring and releasing the game piece have few design constraints with regards to weight, space, work-time, complexity, and motors due to the minimalistic nature of both the drive-train and middle manipulators.

Many robots also have a special feature which adds design constraints not stated by rules.  These design constraints are usually delt with using clever manipulation of the drive base and Middle manipulator, so that the end manipulator has as few constraints as possible.
#58

At least one powerhouse team might disagree with you.