1418 Vae Victis | 2024 Build Thread | Open Alliance

FIRST FRC Open Alliance
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Welcome to the Vae Victis 2024 Open Alliance Build Thread!

Vae Victis is an FRC team based out of Meridian High School in Falls Church City, Virginia. Our first robot was built for the 2004 competition, making CRESCENDO our 20th season. This is our second year as a member of the Open Alliance.

We are part of the FIRST Chesapeake District. This season, we will compete during week 3 at Archbishop Spalding High School in Severn, Maryland, hosted by team 4541, the CAVineers. We will also be competing in the week 4 event hosted at our own high school!

Preseason

Unfortunately, a sizable portion of our team graduated last year, and a long-time fundraising partner retired. Our preseason this year was mostly focused on recruiting new members and finding new fundraising opportunities.

Recruiting and Training



Fundraising


How to learn more

During build season, we plan to post weekly updates to this thread covering the most important wins and fails. If something piques your interest, feel free to ask questions and we’d be happy to share more!

For day-to-day updates and gory details, I recommend checking out our channel on the Open Alliance Discord. That is also a great place to ask questions!

For more fun updates, consider checking out our Instagram, YouTube, Facebook, and Twitter (or is it X?) accounts.

Clicky links:

1418 looks forward to a successful season and wishes everyone well in preparing for kickoff!

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Kickoff Recap

It’s finally here! Time to say goodbye to all family and friends for 3 months!

1418 met up at school at 11:00 am. We spent the first hour before the stream reviewing what to expect for today and the rest of the season. At 12, we had a few technical difficulties pulling up the stream, but we got our first impressions of the game before taking a lunch break.


Our first goal was to understand the game manual. We split up into groups to read different sections. Each group compiled the most important details into a slideshow and presented their findings to the rest of the team. If anyone is interested, you can find our slideshow here: 1418 Abridged Game Manual 2024.

The next step was to start brainstorming. We split into 3 groups to discuss possibilites and start drawing out ideas on paper. Each group presented their ideas to the team, who asked questions and fleshed out a few details. We finished the day by discussing our options further and looking back at the game manual to better understand our restrictions.



Initial ideas

Drive-train-wise, we were deciding between tank or swerve, since those are what we have the parts for. From the initial brainstorming, most of us had the impression that tank would be the best choice for our team. Most of the elements that we need to line up with are flat surfaces with space in front, so we don’t expect strafing will be highly necessary. We’re also considering a thin and long robot, and we’re not sure if we have the programming ability to pull off a rectangular swerve. Overall, tank will be a simpler design, allowing us to focus more on our intake, shooting, and climbing. We also might be able to make 2 identical tank chassis, allowing the programmers to start working on autonomous and visioning sooner without having to steal the bot from the mechanics.

We haven’t discussed an exact length and width yet, but we think keeping the robot short would be good. This may be partially out of fear of all the tipping that happened last year with our top-heavy robot, but we’re also interested in fitting under ~2 ft 4 in space underneath the stage. It could be advantageous to have that path open to avoid defense.

Our brainstorming today focused on intake and shooting. We have three ideas drawn out for consideration.

Roller

This design intakes on one side and shoots out the other. That means we don’t need to turn 180° going from the source to the speaker. This design doesn’t have a specialized solution for scoring in the amp or trap, but it may be possible to lob a note in by adjusting the launcher to a high angle.

Forklift


This design would use two forklift-like arms to pick up notes off the ground. The arms would pivot up to hold the note in a vertical position. Moving the intake wheels one way would push the note into the amp, and the other way would land the note in a shooter to be launched into the speaker.

Combination shooter-intake

This design intakes and shoots with the same mechanism. An arm pivots and telescopes from inside the frame to pickup notes from the ground, and perhaps hold the trap flap open. By adjusting the shooter to a high angle, it may be possible to lob the note into the amp.

Personal thoughts

I was surprised to see these two rules this year.

Robots can only extend 1ft beyond their frames, and there are no gaps allowed in the bumpers. That means there will only be about 9 3/4 in of accessible floor space beyond the bumper. Considering the notes are 14 in in diameter, that seems pretty tight. I think it will be very interesting to see how teams reach around the bumper to pick up notes, assuming they want to do floor pickup. I’m also wondering how viable it will be to drive over the notes to pick them up from inside the frame.

Anyway, I hope everyone had a good kickoff! I’m looking forward to seeing how other teams tackle this year’s challenge!

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Just wanted to weigh in here, based on your code from last year you should just be able to change these locations and it will work. We ran a rectangular rev swerve at offseasons this year with no issues, WPILib’s functions worked as expected.

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Mini-update since it’s a hot topic: we’re leaning more towards swerve now.

We are not sure about dimensions yet, but rectangular swerve is also on the table.

I plan to go into this more in a weekly update on Sunday once we have a larger design finalized. If anyone else is weighing tank vs swerve right now though, feel free to ask and I’d be happy to elaborate more on what we’re thinking.

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Week 1 (1/8 – 1/13) Planning and Prototyping

This week, we focused on figuring out what sort of robot we want to build.

Goals

Mechanically, we want to score in the amp and speaker and climb with another robot during the endgame. Once we can do that, we’ll consider adapting our robot to score in the trap. We don’t think it’s worth it to worry too much about the trap right now. As long as we can climb with another robot, that’ll be 8 endgame points, and we’ll just need another climbing robot or a spotlight to get the ranking point. We’re also looking into keeping our robot under 2’ 3” so we can drive under the stage comfortably.

Programmatically, we want to score multiple notes during auto, so we’ll have to be able to intake off the ground. We’re also going to use our limelight to detect the April Tags to help the driver line up at the speaker and amp during teleop.

Drivetrain: Swerve

While we were initially considering a tank drive bot after kickoff, we decided Monday to pursue swerve instead. While a tank bot would probably be viable this season, the increased maneuverability of swerve would still be helpful. Overall, it just gives more flexibility for sliding up to the source and amp, and makes it easier to align with the April Tags.

There were four big disadvantages to swerve based on our experience that initially made us hesitant. Luckily, we mostly managed to resolve these issues this week.

Firstly: Swerve is expensive. We spent a lot money last year on swerve, and given a tighter budget this year, we weren’t sure if it was a good idea to do that again. However, we still have all the modules we bought last year, so we probably won’t need to spend as much experimenting. It was reasonable to just buy two new MAXSwerve modules in case the old ones break.

Second: Swerve is (was) hard to build. Last year, it took a week to figure out how to build our MAXSwerve modules. Honestly, though, I have no idea why that was the case. This year, we managed to deconstruct, clean, rebuild, and wire 4 modules in a single meeting.

Third: We can only have one swerve chassis. Last year, it was annoying to need to figure out how to time-share the robot between mechanics and programmers. There was a lot of downtime where one team was just waiting for the other. Tank would have allowed us to build two identical chassis, completely solving that issue. This year, we’re going to try to get around this by building a chassis sans-wheels out of wood/metal. It should be a good enough model for the mechanics to prototype with, but we’ll have to wait to see how that pans out.

Four: Swerve is hard to program. Last year, we spent a lot of time troubleshooting code issues with the swerve drive. By the time competitions came around, we still had a problem where PathPlanner paths would move the robot to a seemingly random location, making it very difficult to design competent autos. Again, we’ll have to see how it goes, but we should be able to keep improving our code from last year and squash the bugs.


Intake: Under-the-bumper

Another big discussion this week was intaking over or under the bumpers.

We spent some time prototyping potential intakes to get an idea of what would be required for and possible with each intake style. In the end, we decided to go forward with an under-the-bumper intake. Mechanically, we can have the wheels in a fixed location rather than having to move them in and out of the frame. Under-the-bumper is also less likely to break since it’s not in danger of being hit by another robot or running into a wall. While this intake will always be taking up space inside the frame, the hand-off to the shooter will be easier since everything is in a consistent location. It may also be harder for the driver to line this up, but they also don’t need to remember to take time to deploy the intake.


Shooter: TBD

We’ve recently started thinking about the shooter. So far, there are no concrete plans, but we have thought about our design constraints and done some testing. Since we’re intaking under the bumper, the intake will not double as the amp scorer, so the shooter will have to deal with that as well as the speaker. Of course, the shooter must start within the frame perimeter, and we also want to keep it under 2’ 3” so we can drive under the stage. If we shoot on the same side that we intake, that would let us use a single limelight to detect the April Tag at the source and speaker/amp. On the other hand, shooting from the opposite side would let us avoid turning around when delivering notes during auto and from the source. More to come on that later when we figure it out!


Anyway, that’s all I have for this week. We’ll continue to focus on these topics in the coming week. Programmers need to figure out the swerve code, and mechanics will be working on the intake and shooter.

As always, if something here piques your interest, feel free to ask questions and we’d be happy to share more! For day-to-day updates, I highly recommend our channel on the OA discord (1418-vae-victis). I’ve been posting updates every day we meet, and it’s also a great place to ask questions.

Good luck to everyone in build week 2!

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Just some thoughts about the autonomous swerve problems you’ve been having if they are not already solved at this point. This may or may not be the case for your team, but usually when I see that swerves are going in “random” directions, this is because the coordinate frame of the robot is not set up correctly. While this is something that we can fix for tele-op by inverting axes, an underlying problem such as this coordinate frame not being correct will affect autonomous driving. Hope this helps with debugging!

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Week 2 (1/15 - 1/20) Prototyping

This week focused on prototyping and validating our ideas. We plan to start testing soon to figure out the final dimensions and mechanics for our main systems.

We missed two build days this week due to snow, but overall it wasn’t too bad. Personally, I enjoyed the break from school more than I mourned the loss of robotics :P.

Intake

We moved forward with our under-the-bumper intake by determining the heights and separation of our intake wheels and quickly building out test brackets to put them in those spots.

We’re currently developing a gearbox to connect the two axles while spinning them in opposite directions. The gearbox plate also gives us a convenient place to mount the motor. We used laser-cut wood to quickly and accurately position and secure the gears. Some members scoff at the idea of using wood in the final robot and insist that we cut the final design into metal, but imo wood should be fairly considered first :P. Just something to think about.


Shooter

Our current shooter design has two horizontal wheels, one in the back for indexing and one in the front for shooting. We’re thinking about having two shooting angles using pistons. One would be relatively high for shooting into the amp, or into the speaker when up close. The other would be lower for shooting into the speaker from far away, which would help give us more flexibility to avoid defense. The high angle should also be inside the frame, while the low angle could make it easier to go under the stage. We are not using a motor to have a continuous range of accessible angles. Last year, programmers had a hard time setting up the control loop to put our arm at a specific angle. The pistons let us mechanically lock in the shooter to a known consistent angle.

We’re currently working out two things for the final design: how to make the note shoot straight and what angles work best for shooting at our desired targets. If we find a second angle isn’t advantageous, we might just have a shooter that is fixed in place.

Programming

On another note, the programmers are making progress too! Swerve drive is successfully swerving, and we’ve attached our Limelight 3.0 to the test chassis. We plan to start testing April Tag detection and autonomous path following soon.


Field

We’ve also had a team building our field elements. They’ve completed the amp, speaker, and stage. These will be very helpful in testing out our shooter to determine what sort of angle we need.


Anyway, that’s all I have for this week. As always, if something here piques your interest, feel free to ask questions and we’d be happy to share more! For day-to-day updates, I highly recommend our channel on the OA discord (1418-vae-victis). I’ve been posting updates every day we meet, and it’s also a great place to ask questions.

Good luck to everyone in build week 2!

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Week 3 (1/22 - 1/27) Refining Prototypes

This week focused on improving and testing our prototypes to pin down exact dimensions.

We missed one meeting this week due to the fire alarm going off. Reportedly it was just some smoke coming from a malfunctioning water heater motor, so they let us back in the next day without further incident.

Intake

This week, we connected the intake wheels to a motor using a custom-built gearbox. It was very useful to laser cut wood to iterate through the arrangement of the various axles quickly. In the end, we have one set of 4-inch wheels in the front with 0.125 inches of compression on the note to move it inward. In the back, there is a set of 2-inch wheels centered 1.875 inches off to move the note upward.

We’re currently working on making our design more robust and final. The current mounting brackets were just random pieces of metal, so they have a bunch of unnecessary holes and stick outside the frame. We’re also experimenting with a free-spinning PVC pipe in the back to direct the note further upward, though the exact position will likely change as we develop the transition from the intake to the shooter.


Shooter

The shooter team worked on increasing the power so we could make longer-distance shots. By long-distance, I mean not directly up against the subwoofer. Currently, we have 2 motors on each side, with a compression of about 6 inches (opening is ~8 inches). Running four motors was interesting because it seems that the REV Hardware Client can only run one SPARK MAX at a time. We have tested two motors before using two computers, but we don’t have 4 computers with the REV Hardware Client :P. So, we had a little side quest wiring and coding a mini-robot to test this four-motor shooter.

Anyway, the initial tests seem promising. It seems plausible that we’d be able to shoot into the speaker and map with a mechanism like this. Unfortunately, our shots are not very consistent, likely due to the general jankiness of how everything is mounted.

Our next steps will be to copy our dimensions into MAXTube to see if we can get consistent shots. We also need to figure out where our indexing motor is going, and what sort of angles we want to shoot with.


Anyway, that’s all I have for this week. As always, if something here piques your interest, feel free to ask questions and we’d be happy to share more! For day-to-day updates, I highly recommend our channel on the OA discord (1418-vae-victis). I’ve been posting updates every day we meet, and it’s also a great place to ask questions.

Good luck to everyone in build week 4!

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Telemetry tab > Run multiple

:wink:

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Week 4 (1/29 - 2/3) Integration Prep

We had hoped to get the systems integrated this week, but we were only able to start that yesterday.

Intake

Not much changed with the intake this week. We simply recut the mounting brackets so they didn’t stick outside of the frame and added more churros to the gearbox to better support the motor. We were planning to remake the wooden side plates with metal, but we don’t think it’s a big enough deal to worry about right now. If the wood is a problem, we’ll fix it, but for now, it works. We did transfer the intake over to the MAXSwerve chassis as the first step in integrating the systems.

Shooter

Finalizing the shooter was a big blocker for moving forward with integration. We redid the motor mounts and attached an indexing wheel to try to make our 80-20 design as consistent as possible so we could reliably test it and verify it worked. We also needed to find a good way to shoot into the amp, as our initial test of ‘just shoot it in’ didn’t work out. In the end, we put the shooter up against the opening of the amp and added a piece of lexan above the opening of the shooter to act as a slide. When we shoot, the note pops up and tries to bounce out, but the ramp directs it to slide in. Once we got that figured out, we started transferring the design into MAXTube for a properly assembled mechanism. Since the shooter had to be up against the amp, we can’t use that as the starting position, as it would have to be lined up with the edge of the bumpers. So, it looks like the two-position piston solution we originally planned won’t work. Instead, we’re going to add an axel at the pivot of our shooter so it can be motor driven. This is a little nice since it means we don’t need to make space for a pneumatics system, but we’ll just have to make sure the motor can give us the accuracy and rigidity we need for consistent shots.


Bumpers

We also started working on bumpers this week. We’re planning a similar setup to last year, with a single-piece bumper covered with reversible fabric. Since we’re doing an under-the-bumper intake, the bumpers need to be positioned quite high. The bumpers are 5 inches tall, the note is 2 inches thick, and the bumpers must be below 7.5 inches, so there’s only about half an inch of tolerance for getting the note past. We want to make sure our bumpers are consistently at the maximum height, and a single-piece reversible bumper will let us put it on once and secure it there tightly. We also just found it super convenient last year to be able to easily switch the bumper colors in like 10 seconds. One problem we had last year is that the bumper was a bit flimsy around the corners since we could only fit brackets on the outside. This wasn’t a big deal when the bumper was secure around the frame, but it made placing the bumper on a bit more annoying when everything didn’t quite line up. This year, we made sure to use longer screws that go all the way through both boards rather than just attaching the outside corner bracket to the first piece of wood. We’re still waiting on the reversible fabric, but the bumper is coming along very nicely.

Other stuff

We did a bit of planning as to how everything would come together. While the shooter team was working on the MAXTube shooter, we started setting up the support structure for the pivot axle. That let us get an idea of where the electronics would go. With the intake taking up the front half of the chassis, we need to fit most of the electronics under the shooter. To help us out, we’re planning to have two layers of electronics. We also want to fit in two 2x2 tubes for the climbing arms, which will probably be attached next to the shooter’s supports. It’s a bit tight, but I think it will work out. I was originally inspired by team 5119 to mount the pulley motors directly onto the 2x2 tube, but the shooter posts are right there, so they’ll probably have to be sticking forwards. Anyways, this is all just planning at the moment. More on this next week once we actually figure this out.


That’s all I have for this week. As always, if something here piques your interest, feel free to ask questions and we’d be happy to share more! For day-to-day updates, I highly recommend our channel on the OA discord (1418-vae-victis). I’ve been posting updates every day we meet, and it’s also a great place to ask questions.

Good luck to everyone in build week 5!

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Week 5 (2/6 - 2/10) Integration

The robot is slowly coming together. We lost some productivity this week due to many members being sick, which is most certainly not a coincidence. We do at least now have a list of all the things that need to happen for the robot to be mechanically done.

Shooter

The big focus this week was getting the shooter mounted on the chassis. We finished the structure last week, so it was easy enough to get the two pieces together. Powering the pivot was a little annoying though. We started with just a 100:1 gearbox, which didn’t quite hold the shooter still when it was close to horizontal. We tried connecting two sport gearboxes together to get more torque, but the gearboxes did not like that. So, we just left it as a coder issue to send a small amount of constant power to support the shooter. We were worried this would be difficult given our experience with the arm last year, but the programmers got it working this time. This arm is simpler since it doesn’t change length, so that is nice. After a bit of electronics and chain work, we got all the motors running and were able to test shooting into the speaker. It still works, so we didn’t seem to break anything :+1:.


Other stuff

One big problem we still need to figure out is how the notes will get up from our intake to our shooter. We did some preliminary work yesterday adding a panel to prevent notes from going into the electronics and adding a bar to keep the notes in contact with the wheels. We also need to assemble our bumper and get our climbing system set up. And of course, there are lots of electronics to acquire and assemble.


Anyway, that’s all I have for this week. As always, if something here piques your interest, feel free to ask questions and we’d be happy to share more! For day-to-day updates, I highly recommend our channel on the OA discord (1418-vae-victis). I’ve been posting updates every day we meet, and it’s also a great place to ask questions.

Good luck to everyone in build week 6!

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Week 6 (2/12 - 2/17) Mechanics wrap up (hopefully)

This week focused on finishing up lingering mechanics tasks. We still have some stuff to complete, but hopefully, the next few weeks can focus on programmers.

We did have some trouble meeting this week. For one, a fire alarm on Friday interrupted our meeting again. Apparently, it was the same problem with a heater of some sort giving off smoke. Good that it wasn’t anything serious, but concerning that it happened twice.

On a more positive note, our meeting on Thursday was cut short because we were doing an outreach activity at our local elementary school’s STEAM night. Details on that side-project can be found in our channel on the OA Discord: 1418-vae-victis.

Shooter

Last Saturday when we were testing our shooter, our programmers accidently commented out some lines of code. As a result, not all of the shooter motors were actually running while we testing. We did not notice this at first because it seemed to be shooting normally. When we finally realized this, we asked ourselves, “Why do we have four motors?” Looking at similar side-compression designs, most teams seem to only have two or even one motor. So, we took off the bottom two motors, and the shooter continued to work perfectly fine. We’re not entirely sure why our initial tests with two motors weren’t showing this promise.

In other news, we widened the piece of Lexan that was helping the note slide into the amp. Previously the note could get stuck on the upper corners of this ‘amp slide’, but it seems pretty consistent now. This plate is a little problematic for fitting under the stage, but when the shooter is lowered it fits within the constraints fine. We were planning to mount our Limelight under the shooter, so this just means it won’t have as much vertical space (or we need to find a different Limelight position).

(I am disappointed that I can’t arrange these videos into a nice rectangle like the images)

Transition

One big problem that is still partly unresolved is how the note will get from the intake to the shooter. Right now, we’re fairly confident this will be resolved by a third set of wheels added onto the intake gearbox. In our initial test, the wheels weren’t quite close enough to effectively push the note, but this can probably be solved by tweaking the position of that axel. This did make the gearbox quite a bit bigger, which may interfere with plans for the climber motor.

We’re also still planning to CNC a metal version of the intake gearbox. We received the 1/4" thick aluminum plates (the wood is 0.2 inches thick) to do this this week. However, we only have enough metal for one set, so we have to make sure we’re cutting what we need. Cutting the wood is cheaper and faster than aluminum anyway while we’re still experimenting.

Electronics

Since our intake is taking up the front half of the robot, we’ve ended up trying to squish all the electronics into the back underneath the shooter. Conveniently, this is the first year since I believe 2016 when we won’t have any pneumatics, so we at least don’t need to fit all that stuff in. Most of the motors are near the back anyway. The front two swerve modules, the shooter motors, and maybe the intake motor will need extended encoder wires, but that’s not too bad. Also, since we removed two shooter motors, we only have 15 motors now. The big problem is really just being able to tell which wires are which and fitting our hands through to reach what we need.


Bumpers

The bumpers are coming along nicely. I’ve mentioned this before, but we’re planning to have a single-piece reversible bumper. The plan is once we get our robot inspected, we just slide it on and leave it there. We did the same thing last year and it was very convenient. The corners are a bit tricky to get right, but the bumper team figured it out. The last step will be figuring out the mounting. We do need the bumpers mounted pretty close to max height to get the notes sliding into our under-the-bumper intake unimpeded. We can probably take advantage of the bolts holding in the swerve drive like we did last year, though the climbers may impede that plan a little.


Climber

The climber is the last major system we have to worry about. We’re planning on using two Thrifty Bot telescoping tube kits on either side of the shooter, each driven by a NEO motor with a 12:1 REV UltraPlanetary gearbox. We plan to mount the motor on the side of the climbing tube and replace the supports for the shooter with a custom-cut metal plate that also connects to the climbers. The main tubes will be 1/2 in away from the edge of the frame to keep everything within the perimeter. I’m pretty sure these will fit just fine crammed in with the rest of the mechanisms. Hopefully, we don’t have to do anything too silly.

Programming

Mechanics have finished up the most important tasks we laid out last week, so it’s time to let the programmers get some time with the robot. So far, they’ve got the swerve drive working again after fixing a few issues with the CAN IDs.

Anyway, that’s all I have for this week. As always, if something here piques your interest, feel free to ask questions and we’d be happy to share more! For day-to-day updates, I highly recommend our channel on the OA discord (1418-vae-victis). I’ve been posting updates every day we meet, and it’s also a great place to ask questions.

Good luck to everyone in build week 7!

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Week 7 (2/19 - 2/25) Mechanics did not wrap up

We have two more weekends until our first competition at Archbishop Spalding High School in Severn, Maryland (MDSEV). Unfortunately, we were not able to lock into programming and focused most of our time fixing mechanical issues.

Intake/Transition

Note intaking and indexing seem to be working well. The bolt holding the driving gear would self-tighten and cause the gearbox to seize up or self-loosen and fall out. We fixed this by flipping the bolt around rather than attaching it to the motor shaft. We added pegs around the frame perimeter to prevent the note from sliding under in bad places. We added side plates to prevent the note from getting stuck on the edges and bent back the top shooter lexan to prevent the note from getting stuck there. We had to swap out the cut-up green compliant wheels since their external spikes were eating into the notes. But, after all those tweaks, we can now smoothly bring the note up into the shooter!

We also started CNCing a metal version of the intake gearbox. This is the first time the team has used this CNC and the first time this CNC has been used for metal, so we don’t fully trust it yet. We’re keeping a close eye as it cuts to make sure nothing gets loose and smashes into the bit and breaks it (which happened once). We need to talk more with our Design teacher and figure out how to improve the process so this isn’t a concern. We also only have a 1/4" bit available for cutting, so we have to drill out the smaller features ourselves. Still, the CNC has been a great tool for cutting out the profile and bearing holes, and I hope we can use it again!

Small note: we’re cutting the plates from 8”x12” 1/8" thick aluminum rather than the 1/4" thick aluminum we originally bought. Our gearbox design used to be ~8.5” tall, but we just moved the top two churro mounting holes down a bit.

Climber

We got one climbing arm attached this week. Unfortunately, due to the bolt holes not lining up perfectly and the limited space, it was quite difficult to attach the arms, so we only got one done. The arms do at least seem to fit. The motors are very close to the swerve steering motors, but it does fit. We also cut out new climbing hooks from the old 1/4" aluminum plate we’re no longer using for the intake. These hooks have a deep slot that lets them lock into a chain link.


Shooter

One of the programmer’s tasks this week was to tune the feedforward/PID system that controls the shooter’s position. Unfortunately, they broke the pivot twice. Mechanics replaced the reinforced MaxTube bar with some aluminum extrusion. While the aluminum extrusion looks to have less than or equal to wall thickness than the reinforced MaxTube, we’ve never seen a bolt pulled through the side of an aluminum extrusion. We’ve also extended the motor mount and bolted into the other set of holes to give it more leverage against being twisted out by the chain.


There’s been a lot of miscellaneous tasks this week as we prepare the robot for competition, so for more details, I’d highly recommend our channel on the OA discord (1418-vae-victis). I’ve been posting updates every day we meet, and it’s a great place to ask questions. As always, if something piques your interest, feel free to ask questions here as well and we’d be happy to share more!

Good luck to everyone in build week 8/comp week 1!



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Week 8 (2/26 - 3/3) Robot?

One more weekend until MDSEV! The robot is almost mechanically done at this point, and we’ve at least done a bit of programming. Definitely cutting it close. Hopefully, the next post won’t have very much to say about mechanics and will focus on all the awesome programming stuff.

Intake

We finally attached our CNCed metal intake gearbox plates. The bearing holes were a bit small, and we had to drill the bolt holes manually, but it came together nicely in the end! This is the first time I know of our team using a CNC milled part, so hopefully we use it again in the future for strong and precise parts.


Bumper

Our bumper was unfortunately legally questionable. There was a bit too much space in between it and the frame, and the reversible bumper velcro caused it to go too high. Since we have an under-the-bumper intake, it is very important that the note can slide smoothly under-the-bumper. We employed some corrective surgery and just have to remount the bumpers tomorrow to see if it worked.


Climbers

Unfortunately, the climber motors were too close to the swerve drive. It didn’t look too bad, but once we started driving the motors started scraping. For now, we’ve taken one stage off the gearbox (previously 12:1, now 4:1). Hopefully the motors don’t hate us too much for doing this. If they can’t handle the force, we have modified the mounting plates to move the climbers 1/8" out. We’re not confident that the motors won’t shake around and scrape if left by themselves, but we may be able to add a block to keep them separated if necessary.

We also added some cotterless hitch pins to the arms to keep them contained while not in use (hopefully we don’t forget to remove these before our matches!). After some fiddling around with the bolts, we are able to get both arms attached despite the limited space.


Programming

The programmers did get some good work done this week. We still need to set up presets, but in theory, we can align to the April Tags and aim our shooter. We tested the systems integration by running rudimentary cycles, and nothing broke, so that’s good. We plan to spend the next two weeks defining and practicing our teleop controls and autonomous paths.

Anyway, that’s all I have for this week. As always, if something here piques your interest, feel free to ask questions and we’d be happy to share more! For more details, I highly recommend our channel on the OA discord (1418-vae-victis). I’ve been posting updates there every day we meet, and it’s also a great place to ask questions.

Good luck to everyone in build week 9/comp week 2!

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Week 9 (3/4 - 3/10) Practice (Finally)

MDSEV is this weekend :grimacing:! We finally started really working on autonomous and doing teleop practice, stress testing the robot and such. Would have been very nice to have more time, but whatcha gonna do.

In other news, we had Senior night this week! While we only had 2 seniors, we celebrated with their families and gave them their parting gifts (a Capri sun, balloon animals, and their FIRST graduation cords). It was tons of fun and we got to celebrate how far we have gotten this season!

The sophomores also surprised everyone with a happy birthday cake for the seniors!

Okay, okay, Mechanics still have to do a few things

The mechanics spent some time finishing up odd tasks like adding handles to the robot, assembling our spare MAXSwerve modules, and creating spare parts for the things we think are most likely/most annoying to break. The bumpers are now properly attached at the right height so the note goes under, but the fabric is still in the bumper zone. We made a mount for the RSL and added surgical tubing to keep the shooter in the starting configuration when depowered. We also went through the inspection checklist, and everything is looking legal.


There are still a few problems left to solve. The shooter/climber structure is a bit wobbly, so we need to take some stuff apart to reinforce the crossbar. The climbers are also not quite powerful enough. We’re waiting on some 9:1 MAX Planetary gearbox modules to replace our 4:1, and may stick some ratcheting wrenches in there to stay climbed after the end-of-match disable.

Autonomous

There were a few programming errors to solve before autonomous worked (at least a little bit). Some code for controlling the shooter pivot was mysteriously missing, causing it to never slow down. There also seems to be an issue where the coordinate frame is inverted somewhere. We managed to get around this and got the following auto working, though we’ll probably need to do some major debugging before we can make good autos. Hopefully, we can at least get one two-note auto working consistently.

Teleop

We assembled our drive team and started practicing our cycles. A bit of programming was needed to get the shooter angle and limelight presets setup, but then we spent most of yesterday and today practicing. It looks like we still need some more time to get used to the controls.

Anyway, that’s all I have for this week. As always, if something here piques your interest, feel free to ask questions and we’d be happy to share more! For more details, I highly recommend our channel on the OA discord (1418-vae-victis). I’ve been posting updates there every day we meet, and it’s also a great place to ask questions.

Good luck to everyone in build week 10/comp week 3!

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Week 10 (3/11 - 3/17)

We’ve finished our first competition! It went all right, and we definitely have some things we want to improve. Next comp is this Friday again, week 4 VAFAL. We’re hosting this one at our school, so that should be some extra fun!

Preparation

First, a recap of the things we did last week before the competition.

A big mechanics task was reinforcing our main climbing/shooting structure. This didn’t have quite enough support and got quite wobbly (foreshadowing). Unfortunately, our bottom electronics was in the way of this installation, so it took a while to get that off and back on.

While rewiring the bottom panel, we made a few mistakes, including swapping the output power wires of one of our steering motors. This killed the 550, so we quickly swapped out the module, which was at least good practice (foreshadowing).

One of the ropes for our climbing arms had a too small knot and slipped through the bottom block. We pulled that out from the bottom of the tube and tied it around a washer so it didn’t slip through again. On a positive note, we fixed our climbing problem using a 9:1 gearbox module and some ratcheting wrenches. The robot can pull itself all the way up without the motors dying, and it can stay up after disabling. The wrenches have a little lever that switches their direction, so we don’t have to take the wrenches off to release and reset the arms.

MDSEV

Qualifications

One big unresolved problem is that our climbing arms tend to get stuck near the bottom of the tube and don’t move up when we unspool the rope. To get around this we just started the climbing arms at a higher point where they don’t stick. Unfortunately, this meant we had to sacrifice the ability to go under the stage, which made it hard to navigate and avoid other robots.

Our climber/shooter structure was still wobbly, so we added a tensioned rope in the back and a metal foot on the side. While these were just quick additions, they were pretty effective, so we’ll probably be keeping them.

In a few matches, we had a problem where the robot would stop responding for about 6 seconds after big hits. Expert advice indicates that this is probably a wiring issue causing the RoboRIO to cut out for a split second, but not long enough to do a full reboot, which would take noticeably longer. Unfortunately, since our RoboRIO was hidden on the bottom electronics panel, it was hard to diagnose or try to fix this problem.

One match, we believe the drive motor key fell down into the absolute encoder bridge in one of our MAXSwerve modules, causing the wheel to lock and the motors to become quite hot. We were luckily able to swap it out fast enough to make the next match.

In two of our matches, we got a note stuck on top of the intake and couldn’t score anymore. To hopefully avoid this, we remove the front camera mount.

Overall, matches started off well but went downhill in the end. I don’t think our mechanical issues hindered us very much; we were just outplayed. We were unfortunately not able to get the bonus ranking points for melody or stage points very often. We ended qualifications ranked 22/36.


Playoffs

Despite our troubles, we were first pick for the 8th alliance with 8726 CryptoHawks as captain and 1719 Umbrella Corporation as our partner! Big thanks to them for being great teammates despite the fact that everything literally fell apart in the end.

The 8th alliance faces the 1st alliance in the first playoff, which we generally did not expect to win. Alliance strategy placed us in defense to hopefully prevent the 1st seed from completely outshooting us. We adopted a special formation with the goal of avoiding damage.

That may have backfired and pulled the shooter apart, causing us to lose most of the hardware for one of our shooter wheels. Playing defense was rougher than expected, and most of our electronic system got messed up as well.

Our alliance partners didn’t fare much better in that match, and we were all barely able to get back for the playoff against the 5th seed. Shoutout to 6213 for subbing in for 8762 there! Unfortunately, we lost that match as well for a swift double elimination.

We earned 20 district points, placing us 19/36 for the event and 72/135 currently in the CHS district.

Plans

Luckily, nothing major broke too badly. We will have to rebuild one shooter wheel system since we mysteriously lost all the pieces when the shooter split apart.

A big goal is to confidently drive under the stage next competition. We couldn’t do that this week due to our climbers getting stuck if we put them all the way down. To fix this, we plan to shave down the internal blocks and cut a bit of height off by modifying the hooks.

We also want to reorganize our electronics to put the RoboRIO on top. This should make it easier to debug future connection issues and perhaps avoid any tension that may have been messing with the power wires.

Programming-wise, we need to look at limelight and autonomous. These were acting a little strangely, so we mostly relied on manual control, which hurt our accuracy and speed. We want more reliable and versatile options for autonomous.

Only four meetings available to do this, so we’ll see how it goes.

Anyway, that’s all I have for this week. As always, if something here piques your interest, feel free to ask questions and we’d be happy to share more! For more details, I highly recommend our channel on the OA discord (1418-vae-victis). I’ve been posting updates there every day we meet (including match-by-match coverage of our event), and it’s also a great place to ask questions.

Good luck to everyone in build week 11/comp week 4!

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Week 11 (3/18 - 3/24) Season Finale

Our week 4 VAFAL competition went much better than MDSEV! Maybe it’s the home team advantage, but we ranked 4th in qualifiers and 3rd overall for the event! This placed us 30th out of the 54-team capacity for the Chesapeake District Championship. Unfortunately, we have decided to end our season here and pass up the chance to go to districts. More on that later.

Preparation

After MDSEV, we identified a few priorities for repairing and upgrading the robot, and we just about squeezed everything into our 4 days of meetings.

We cut down the climbing tubes and climbing hooks in order to fit under the stage more easily. The lowered height was reduced by 2 inches, and the extended height went down 3 inches. We also shaved down the internal blocks so they wouldn’t get stuck at the bottom of the tube. While this made the arms a bit more wobbly near the top, we didn’t have any more problems with the climbers.

We also reorganized all the electronics to put the RoboRIO on top. This involved unplugging and taking off everything, which we were luckily able to do mostly in parallel with the climber updates. Previously, the RoboRIO was hidden on our bottom electronics panel underneath our PDH. While not illegal, this made it hard to troublshoot the connection issues we had at MDSEV. To avoid damage or interference from errant notes or the wires on top, we put the RoboRIO into a little box.


We also swapped out the treads on our swerve drive. These Thrifty Bot wheels lasted very well. I believe we installed the treads pictured below for our second competition last year, and they held up without any noticeable problems. We had a slight suspicion they had finally worn down enough to throw off our auto a bit, so we finally put in new treads.

After that, the programmers had just enough time to get a middle two note auto working. This worked very consistently when we could use it, but the lack of flexibility sometimes meant we had to let another team could get more points from the middle position. We could just about shoot one note from the side positions and sometimes LEAVE, so it would have been nice if we gave our programmers more time to expand our auto capabilities.

VAFAL

Set up

This week’s competition was hosted at Meridian High School in Falls Church City, Virgina, which is our school! This was the first time 1418 has hosted an event, and I have to say it was very fun to see how everything gets set up. Even with all the team members skipping class to help, it was still a lot of work.



Our mayor and superintendent came to speak at the opening ceremony, as this is the largest indoor event hosted at the new high school built 4 years ago (basketball only takes up one gym :P). We’re super grateful to the school and community for helping make this event and the team a reality!

Qualifications

We now believe our comms issues last week were (at least probably mostly) due to a bad ethernet to USB-C converter. After swapping out everything else on the robot this was at least the last thing we tried. We didn’t have any more communications problems, so that’s good at least.

We also decided to put the front USB camera back on. To avoid getting a note stuck again, we added a string, which looks a little goofy but was easy to do and worked pretty well~ Reportedly, it saved us two times.

Overall, we didn’t have many problems during qualifications. A few times, a loose wire came out and messed with our intake, a climber, and maybe a swerve module. We also had the battery lead disconnect once, luckily not during a match.

We got super unlucky with our match schedule though; it’s kinda silly. The first day had us swapping colors every match, and we had three 3-match turnarounds. Reversible bumpers were great for this, but it’s also good we didn’t have any big problems to fix.

A high point of the quals was #66, where our alliance handed 1731 their only defeat of the competition. I believe this was unfortunately due to 9033 being out of commission, though the match was still very close!

We ended qualifications ranked 4/34!

Playoffs

We were the 3rd seeded alliance captains and chose 1895 Lambda Corps and 2186 Dogs of Steel.

We handedly won our first two playoff matches with a note stockpiling strategy. We were also able to harmonize with 2186, which was a nice boost when we gave it enough time to work.

Unfortunately, our robot spontaneously ripped apart for seemingly no reason. At the end of match 8, you can see the structure suddenly disconnect when just hanging around. From what I can tell, the 16 rivets we added before MDSEV simply disconnected, causing the whole climber/shooter structure to disconnect from the chassis. The outer casing of the climbing motors also coincidentally both fell off.

We decided that it would take too long to fix this, and without our shooter and climber, there wouldn’t be much for us to do. So, we called in 5243 Aegis to sub.

Unfortunately, we promptly lost matches 11 and 13 to get double eliminated. Our alliance still competed wonderfully without us; they were simply outplayed. However, that still means we made it to semi-finals!

In the end, we earned 51 district points, placing us 3/34 for the event and 30/135 currently in the CHS district.

Awards

We won the Team Sustainability Award at VAFAL.

Also, I forgot to mention it last week since I didn’t have a picture, but our safety captain earned the Safety All Star on day 2 at MDSEV!

Tear Down

Shout out to everyone who helped clean up the field and pits! While building is usually harder than destroying, it still went much faster with all the help!


Plans

As I mentioned at the start of this post, we’ve decided to decline the opportunity to go to the FIRST Chesapeake District Championship. While we probably could have rebuilt our main structure before the competition, we all decided to take a break. Unlike last year, districts is neither close nor during spring break, so it would have taken a lot of physical and mental resources from the team.

We are still planning to repair MANTIS for our post-season outreach and recruiting events, and perhaps a preseason competition next year. For now, though, this is the end of this build thread! As always, I’m still happy to answer any questions here as long as replies are still open. I also recommend checking out our channel on the OA discord (1418-vae-victis) for more details. I’ll be posting updates over there as we continue our off-season activities.

Good luck to everyone for the rest of your robotics season!

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It was more than great to compete with y’all this season! I wish y’all the best of luck in your post season and pre season activities now :blush:

Go 1418!

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