Team 2980 2023 Open Source Thread

eedoga · February 12, 2023, 6:14pm

So…I am pretty much the only mentor that does design work. Historically we had a CADD sub-team that did 90% of the CADD work before we started building. Between the pandemic and the past couple of years of recovery we haven’t really had many kids capable of doing design work, so the design process has been stretched out a whole lot more and the prior anonymity of having a team doing the design work is gone.

So…the problem is two fold. On the one hand, the kids who are currently forced into doing the design work don’t like to do it and sometimes do sloppy work as a result. Less than optimal solutions based on ease of CADDing or not thinking a problem all the way through, only to be dragged by the part of the team who isn’t willing to take up the challenge at all. There is also a lot of hindsight complaining.

Honestly this is probably not as bad as I make it sound, and I love my kids. We are just growing through some things as we build back after the pandemic.

We will get back to where we were some day.

RogerR · February 12, 2023, 8:24pm

Feel free to ignore my advice; you know your team better than some dude on the internet; you’ll know what’s best for it.

I definitely understand the impatience inherent in CAD design, especially if it takes a while to fabricate, or requires a lot of iterations, is subject to review/heckling, etc. Depending on you team’s skillet, maybe more parts can be made by hand, without CAD? One of my favorite design methods is “CAD-Cardboard Aided Design”, where you design your workpiece out of cardboard, before transferring onto sheet metal (or delrin, or polycarb, or plywood, etc.), and fabricating it with traditional sheet metal tools. This is especially useful early in the season, when prototyping. A few years ago, when we had a ship /bag and tag date , we would build two robots, so we would rarely do that on the final bot, because we wanted both bots to be identical. Now, without the cutoff date, we build just one, and a bespoke robot isn’t as big a deal.

If you’re able, having mentors help with student designs (or students help with mentor designs) may help with several levels. They may catch student issues (and vice versa), and it may pull some pressure from them during the design reviews; I’ve found with younger designers, they sometimes are a bit less timid when they work on “my” designs. I suspect there’s some presumption that I know what I’m doing, so they feel more confident, plus if it’s a bad idea, it was “my” bad idea.

eedoga · February 14, 2023, 6:39pm

So over the last year or so our team was able to acquire access to:

A waterjet,
A CNC plasma cutter,
A large format CNC milling machine,
And an SLS 3d printer.

At this point these kids should be making very little by hand.

That said, where Cardboard aided design can be a good thing, is in the initial steps leading up to CADD. Make the thing using a paper or cardboard template, then use that to get your measurements and drop the whole thing into the CADD model.

I would have absolutely no issues if that was what was happening.

Reality is, I don’t have much to complain about at all really.

The kids are making progress and things are at least thinking about coming together. Fingers crossed they actually work the way the kids expect them to and we don’t have a total nightmare on our hands.

We should have a much more clear picture by this weekend.

Edoga

eedoga · February 15, 2023, 5:56am

Being negative

Sorry if I sounded too negative in the past few posts. We are at that stage where everything is still very up in the air, and while it works in theory, theory is a wonderful place to live, and for some reason the team is moving really really really slowly this year.

But…I think things will come together.

Not sure what my “ace in the hole” might be, but hopefully I can come up with something to help get them across the line in the event that something doesn’t work the way they think it will.

The robot is close weight wise.

Not sure how close.

I picked it up today and it felt…close…Not heavy yet, but pushing the boundaries, and we still have a few things we need to add. Good news for the kids though, I’m not at my strongest right now, so my internal scale may be off by a bit. That said, if it is a choice between a heavy solution to a problem and a light one I bet you can guess which one I am going to lean towards.

We also need to save some weight to act as a counterweight for the arm.

The kids are doing outreach tomorrow for a STEM night in the neighboring town. Bad timing but what can we do?

Yesterday I had a doctor’s appointment and missed the meeting. Nothing big, just meeting a new doctor and setting up a plan. Of course this one needs to do all the tests over again because he wants to see for himself, So…It was really just an opportunity for me to get off the island and get foods that I can’t get locally.

Thing is, me not being at the meeting…I am starting to wonder if I am pushing too hard, or inserting myself too deeply in what the kids are or aren’t doing. Maybe I’m steering the ship with too firm of a hand.

They came up with a solution to a problem and my first answer was…THATS THE WRONG ANSWER! But…it isn’t, and we should be able to make it work. It is an answer, and the kids are doing what I want/need them to do. They are solving problems.

So…I am thinking I need to schedule more doctors appointments? Or maybe just take more of a back seat and see if they actually do the things. Maybe I’ve been the problem all along.

Guess I’ll have to dedicate a yoga practice and some meditations to this one. Honest I’m trying my best.

Nuff for now.

Edoga

eedoga · February 17, 2023, 5:44am

Something to listen to?

The girls camped out in front of the fire. They are definitely well aware that I am spending too much time at work at the moment.

Something I should say before we continue having this conversation:

These words and thoughts are my own. This truth is my own. This is a lot like when you think back on some experience you had and asked a friend to tell the same story, it would sound similar but different in so many ways. I try to speak for myself.

I do this in the hopes that other teams having similar experiences understand that these things are the normal course of things. Perhaps they shouldn’t be, and in a perfect world there would be a better way, but…If there is, I haven’t discovered it yet.

This is an open source thread…Yes, but the main goal is to be open about the experience in addition to being open about the robot, so that everyone can understand that the stress and hardship of the “hardest fun you ever had”, is almost universal.

We lifted the arm by turning the hex shaft that drives it using a half inch wrench. It wasn’t too hard to lift, but it was also not fully extended. I was thinking about adding a small piston that would act as a break stopping the arm from swinging back after it gets where it is going. I suggested it. Haven’t gotten much of a response yet.

Showing how far we need to lift the arm and how far it will need to extend in order to reach the top post of the grid. We may end up going second level only for our first competition, but fingers are crossed.

The gearbox that runs it all. It is a gearbox meant for the output of a stepper motor but we are making do.

I woke up this morning completely shocked. I felt like I rose up out of my bed fully awake and with full understanding. I realized something and I think I have a new understanding of at least part of what is wrong.

So…I suppose the symptoms of a problem and the actual problem are two different things. So…First up, the symptoms:

Our robot reveal ceremony is on Tuesday and
The arm hasn’t moved under its own power and we don’t yet know if your setup is strong enough to make it happen.
The arm currently has a clamp on it because we haven’t finalized the inny outy part yet and while yes, we are waiting on smaller sprockets and chain, we could make it work with what we currently have on there if we needed to.
The intake is on the robot, but we have a really complicated way of making it go up and down that we just started thinking about yesterday.
The landing tray, a flat place for cones and cubes to go when the intake is done intaking doesn’t exist yet. (this one is really easy
The gripper has no gripper yet. Only the part that goes clampy clampy but no arms or place to do that grabby grabby and I finally caved and started working on that with a kid yesterday.
The last time I checked one of the swerve wheels was pointing off in a random direction
We haven’t weighed the robot. I can still pick it up by myself, not recommended if you don’t want to have a bad back, but there is still more to go.
No subsystem on the robot is complete.
Several parts only exist in people’s imaginations

Yet still…over the past two days I have seen my team begin to think about rising up out of its slumber.

We set a rule yesterday. Everyone had to do…Something to do with the robot. Everyone had to bend a bracket, or drill a hole, or file off something sharp. Everyone. No one could do nothing. Everyone had to be included.

It was wonderful.

Most of the team’s go getters were off giving a presentation at a STEM night in a neighboring town, so it was mostly the kids who come to robotics because it is a cool place to hang out. Our art kids. Our kids who hang out in the hallway because it isn’t home. All of them, and even a kid who isn’t on the team at all, but seems awkwardly interested in a girl who is.

And while I watched them talk past each other and fail to recognize what each of them seems so intent on expressing, they filed a sharp edge off of the robot. They used the metal devil miter saw to cut a shaft, and they filed the edges off of a part fresh off of the plasma cutter.

These are the kids who mostly hide in the back of the room claiming to be making art for buttons and stickers while having strange conversations about which transformer is the best.

But they worked.

Today I tried to have the same rule. Not the same level of success, but progress was still made.

Some of the more ambitious kids were back. Probably going to have to go have coffee with one of them. Might just let him use it as a clearing. Let him yell at me to get it out of his system so he stops taking it out on the rest of the team.

Or I might remind him that he wants to be in a leadership position at competition, and that he is doing the very same things that got someone else removed from a leadership position last year.

Not really sure how I’ll play that one.

I can’t say I can see the light at the end of the tunnel yet, but maybe the tunnel has lightened enough for me to begin to make out the features of my hand as I wave it directly in front of my face.

Ok…Enough for now.

Edoga

eedoga · February 17, 2023, 9:39pm

So…this is frightening…

I checked the table and our setup should be OK, but the idea of having the arm chew through a bunch of gearboxes is more than moderately frightening.

I came up with a solution if it does start to happen, but man…I would prefer to not have it be an issue at all.

So…The current setup:

Stage 1 and 2 are at 5:1 = 25:1
The worm gear is running 15:1. I think we have some 20:1 on order.

So…the fix?

Offset the whole shebang by 4 inches, basically whatever the limit is so we are under the height limit, and then use sprockets and chains to transmit power to the main shaft. Given the sprockets we currently have in stock our options would be pretty limited. so We’ll have to make do with what we have available for now.

might try cutting out our own gears using scrap metal and filing the edges to make the whole thing work until ordered gears can come in…

This whole panicked fever dream has happened repeatedly today…And the reality is, I have no idea if any of this is necessary. The whole thing might work just fine.

I’ll keep you posted.

Edoga

RogerR · February 17, 2023, 9:54pm

Any idea what the torque rating on the worm gearbox is?

sethP · February 17, 2023, 10:08pm

do you need that much torque? with 1 NEO that is about 350 Nm (~258 lb-ft) of torque while current limited to 40 amps which seems like well above what you should need for anything in FRC use. also we should have some spare 5:1 VersaPlanatry ratios we don’t need if yours break at glacier peak

eedoga · February 17, 2023, 10:14pm

It looks like it is a bonfiglioli gearbox. It was donated years ago. No idea where it came from. it has .25 hp stamped on the side. so not a torque rating per say and is 15:1. We have used it in a winch to lift the robot multiple times. We ordered two of there:

At 20:1 in case, but I know even less about those. The new ones won’t be here until the 3rd, our first event start date, so if this goes we are going to have to figure something out in a hurry. We do have an andymark 20:1 regular gearbox from years ago but that would pretty much be the nightmare scenario.

beedward · February 18, 2023, 2:27am

Looking at that gearbox I think you’ll be fine, it looks pretty robust. I think you’re more likely to twist the long hex shaft than damage the gearbox. Also the VP will not have issues, you’re using the strongest configuration and a shaft coupler instead of the fragile hex output adapter. The worm drive gearbox should prevent back drive from damaging the VP.
We’ve had problems with Versaplanetaries in cases where back drive and shock could damage them, when we used the female hex output coupler, and when we used 10:1 stages. 5:1s are much stronger.

eedoga · February 18, 2023, 3:41am

Thanks for the words of comfort.

Yeah…the hex shaft is a concern. We swapped out the aluminum one for steel. I should probably check in Autodesk inventor to see what we are looking at.

At one point we considered stepping up to a much larger shaft, so 1/2 inch hex to something like a 2 inch aluminum shaft…Might end up there anyway.

Edoga

s-neff · February 18, 2023, 3:46am

You’re fine. 5:1+5:1 is a great Versaplanetary set, and the worm gearbox won’t let shock loads roll back through into your gearbox either way. I’ve only ever mulched 10:1’s, and it was in a setup like that thread’s OP (though, only 100:1 overall, and I did have a chain after it but the cantilevered gearbox output still did me in).

I’d keep the 1/2 hex, so that the 1/2 hex breaks before your mounting plates bend and let the gearbox get out of alignment and crunch. Remember, something must break first, so something easy to replace like the 1/2 hex axle is a great place to plan for that.

The stuff that doesn’t exist yet seems more important to work on first

thehotbotz2640 · February 18, 2023, 5:58am

I’m so encouraged by this thread. This sounds like our journey in many ways. It’s comforting to know we are not alone.

eedoga · February 21, 2023, 6:19am

Every circuit has a fuse.

So…This gearbox decided to eat itself.

The worm wheel came apart into several pieces.

That isn’t to say that there weren’t plenty of other problems, and on one level I am really glad that if it had to happen it happened now instead of during our first match…But I sort of wish it had happened a week and a half ago.

So…Scramble city.

Here is the first part of the solution that we came up with:

So we started converting the two vex planatary gearboxes so that their output is the cim output, and we are digging out our old gearboxes to find something that will work. The chain - sprocket will also gear things down? up? I can never remember which way it goes, but the big gear will have 60 teeth and the small gear will have some number less than 60…I know…not real helpful.

The kicker is, we have to remake the entire arm in order to do this. So…Off we go remaking the entire arm.

I feel really bad for the kids. A couple were crying over it all. We have our presentation to the community tomorrow from 6-8.

And a community outreach event on Friday?

Not the best timing.

Ok…I’ll write more coherently tomorrow.

Enough for now.

Edoga

eedoga · February 22, 2023, 5:32pm

I wrote the following yesterday but I didn’t have time to post it before the community robot reveal event.

While the arm design had a load of problems, having the worm wheel give out…

Well…This will inspire something new, hopefully something better. Then again, the thought that we can do something in a week when the thing we worked on for 6 weeks didn’t work isn’t really inspiring. Hopefully we can look at the past 6 weeks as training for right now.

It isn’t back then:

So…If it was pre-2020 we would be putting a broken robot into a bag today.

Hopefully I would have convinced the team to build 2 drive bases, and we would be withholding the arm in order to make adjustments, hoping that we could keep it under 30 pounds.

The team would be writing down procedures for what they would do in order to install the new arm on the robot when we got to the competition…And they would learn about how two drive bases that were supposed to be exactly the same are actually different, and how those differences are all the world between success and failure.

But it isn’t back then.

If it was back then, we wouldn’t have gotten into this mess in the first place because we would have finished the build by week 5 at the absolute latest.

We would have focused either cones or cubes, and we would have focused on the first and second level.

Our drivers would have had plenty of practice time by now.

But it isn’t back then.

The team would have 40 people, all fighting each other for the slightest job or thing to do. And another 10 focused solely on awards.

But it isn’t back then.

If it was back then, our bumpers would have been done by the end of week 2, and by now we would have rubbed the numbers off of them repeatedly driving the robot through the doorway with the bumpers on.

But it isn’t back then.

So…Instead, it is now.

The arm is broken, but there is a pretty solid plan on how to fix it, and we have a few more days, and a whole weekend to get the job done.

What we weighed of the robot, and some other stuff we thought we might possibly use before the worm gear ate itself came in at a healthy 112.5…And really I can’t imagine them getting too hung up inspection wise.

The drivers can get some practice putting the robot places and doing really unbelievable balancing on the charge station while the rest of the team builds 2 different arms to make up for the broken one.

And hopefully, in the end we will have a robot that is middle of the pack. Nothing too flashy, nothing too bad.

Well…Fingers crossed…And toes…and anything else that you can think of.

It’s not whether you get knocked down, it’s whether you get up.
Vince Lombardi

Enough for now.

Edoga

eedoga · March 2, 2023, 9:32pm

You go into battle with the army that you have, not the army that you want.

I think…if I were a robot inspector…I might ask the team to cover this open sprocket with a guard.

This is the way in which we fixed the broken gearbox issue. Probably should have done things this way to begin with. The small sprocket is driven by two NEOs at 5:1 going into a 10.75:1 gearbox. This then turns what I think is a 15 tooth sprocket which drives a 60 tooth sprocket…So…two neos at 215:1?

It all works pretty well, but again, we should probably put something over it to keep curious fingers out.

This is our gripper. The plate has curved slots in it which transfer the force from the piston from vertical to horizontal, making the gripper pads which are mounted on servos slide in and out.

The gripper itself is made of a 2 inch memory foam pad with a soft rubber material sewn over it.

Our first competition starts tomorrow.

At least 1 set of bumpers are a quarter of an inch too high on one side.

This is an absolute nightmare of course…Sort of hard to move a hole.

If the bumpers were way off, it would be easier. We could just make new holes, but…because they are where they are and the difference is so small changing things at this point are going to be pretty difficult…Or will it?

So…
A. be backed by ¾ in. thick (nominal, ~19mm) by 5 in. ± ½ in

Does this mean we can cut .25 inches off of the top of the backerboard and be…OK?

It seems like a horrible solution because it would mean resewing the bumper fabric on that side…But…it may beat the alternative which would be redoing the bumpers entirely.

And…I spoke too soon.

The brackets holding the bumpers in place have bolts sticking out of the back of them holding the bumpers at least ¼ inch away from the sides of the robot and the holes for mounting the fronts and backs of the bumpers won’t line up anymore. So…I guess I’m getting a couple project boards at the local big box store during my lunch and cutting them into nice straight 5 inch wide strips so we can rock and roll redoing the bumpers this afternoon.

This is really on me. While I did ask the kid making the bumper backer boards questions, I should have been more insistent on making sure they were doing things right.

Ok…so…one problem.

Really though things aren’t as bad as they could be.

The drive team has had some practice.

While our intake does not work as intended, neither does the cone scoop, the gripper currently works well enough to load upright cones and cubes. And the drive team has actually driven the robot around and maybe scored a point or two.

We might be able to place a preloaded cone during autonomous.

Really…things are looking up.

Just need to get past the bumper snafu.

So…What else?

I feel like it is way too early in the competition season to be this tired. I feel like I am barely meeting the minimum of all of my obligations each day, and I keep waiting for the fever pitch of our season to break. I keep thinking…Ok…so just one or two more days of going flat out and then you can relax…

So…now I’m trying to convince myself that if we just make it through this first competition then I can relax, but the reality is the kids have really big plans for the second competition. Getting to score on the 3rd row by adding another level to the arm for example, and converting the intake to something that looks more like the everybot intake, and hoping that it will work better than what we currently have.

Did I mention they want to repaint the pit.

I feel like there is more.

Oh…yes. They have a few outreach events between competitions. A lego camp in a neighboring town along with some presentations. They also have a project on the south end of the island…

So here is the strange part.

I started out this post feeling like I
Don’t have enough kids on the team who are actively involved in the robot. (that number is somewhere around 8.
Am working the team way too hard causing burnout and sickness.

But, the last couple of lines reminded me that while, yes,
the robot is worked on and understood by a small group of kids,
The rest of the team is more than willing to do all of the other stuff.

Maybe the balance is off by a bit and maybe we should have worked things out a little better based on the time and human capital we have available, but in reality my cup runneth over.

Now I just have to get them through this weekend and I can finally relax.

Ok…I’ll try to keep you posted about our progress this weekend.

Nuff for now.

Edoga

eedoga · March 3, 2023, 5:48am

I managed to salvage the blue bumper fabric along with the numbers.

Only stabbed myself in the hand 3 times…

Not all is lost.

Edoga

eedoga · March 7, 2023, 3:59am

Losing sight of what is important…

So…Our first day of competition was a dumpster fire.

Our drivers didn’t have enough time to practice with the robot that we built, so in the first match when they tried to balance on the charge station the robot tipped over landing on its back…hard.

After that we had electrical issues for 6 matches, missing 1.

The radio had connection issues for several matches so they replaced it, and then ended up recoding the original.

The roborio kept losing power. Jim Wright was able to identify the problem there…The servos we used positioning cones drew too many amps browning out the roborio when they stalled.

The kids gave up on the intake, removed it, and added 8 pounds of weights to the bottom of the robot (getting reinspected caused them to miss a match.)

And finally the gripper ripped out the robot’s battery plug because it got caught on the servos that we had already identified as the problem and unplugged.

So…6 matches of absolute sadness.

The booster club/parents were seething. I had to coerce one of our newer mentors out of the pit and again, Jim Wright came in and saved the day, talking the guys ear off and introducing him to as many other mentors as possible. (have I mentioned how much I look up to that guy?) Parents were asking questions like, “Are the kids in the pit even capable of diagnosing what is wrong?”, “Why can’t our kids build something better than a push bot?”, and “If these kids can’t get something to work then we, the board, are going to be hard pressed to spend any more money on anything for them this season.”

And…my heart broke a little.

See…the hard part is that leading up to this competition I sort of realized that I really have 6-8 robot kids that actually understand the robot and what went into making it, and a couple more that are trying to learn, and while on the surface that would/should be enough, in a post covid reality where parents don’t understand what a commitment this can be, and kids don’t understand how much goes into this, 6-8 isn’t enough.

And it was after the gaggle of parents started piling on that I realized just how wrong we were being about what was happening.

For the past two months we have been telling the kids that it is not about the robot, and pulling them off of robot stuff to have them do stem nights and presentations and workdays at the tiny home village. We have been having them focus on an impact presentation even though we know they aren’t going to win. We have been having the work on a girl’s day and so many other things, and telling them that the robot is secondary to all of that.

But…then we come down on them hard when things don’t work out the way we want them to.

We forgot that it is just a game, and winning just gets you more chances to play.

We aren’t jack in the bot…we aren’t going to be any time soon.

We are who we are, and it is high time we recognized that.

Day two was better. The kids placed game pieces in autonomous scored a link, and attempted to balance on the charge station. They came up with a plan for modifying the robot for their next competition, and were even selected in the first round of picks for the 8th seed alliance.

In the end, they even did well in the robot category.

So…We forgot what we were really doing, and they remembered.

We…the adults, will have to work on this.

Enough for now.

Edoga

MikLast · March 7, 2023, 5:32am

Eedoga, I’m fairly sure you’ve explained why 2980 does their build season this way before, but can you explain why your designs are picked by the community? This year, it seems like they set the team down a path that wasnt very realistic (as you said yourself earlier in the blog);

and the first quoted comment irks me a bit considering it was, in part, their choice to build this kind of robot, even if the kids may of struggled to fully explain all the pros and cons (which you hit on shortly after the 2nd quoted part).

eedoga · March 7, 2023, 6:12pm

The parent reaction wasn’t universal.

That said, I think it was a combination of misplaced anger (disappointment in things not going well) and a lack of understanding of the situation. This was clarified during our team meeting over dinner Saturday night.

Really…The kids did a great job all things considered.

I’ll write more later.

Edoga