1339 Open Alliance Blog 2023

Hello Everyone,

1339 is once again participating in the Open Alliance build for the 2023 game. OA has grown to include more than 80 teams with a core mission of openly sharing ideas, processes, failures, and successes so that more FRC teams can be competitive. Last year our team experienced firsthand how impactful this mission could be; we interacted with dozens of teams who used what we knew to make their robots better. In competition we found that not only were there teams who benefited from our shared insight, but we ourselves had our most successful season ever, at least in part because the Open process forced us to consider our decisions very carefully.

With so many teams participating this year, we are planning on contributing in more focused ways than just creating a build blog. While we will be posting frequently, it will not usually be about the routine decisions of Build Season. Here (roughly) is our plan for the season.


We have a large team right now (by our standards): 50-ish students and 11 mentors. Though some of our students are focused exclusively on projects that don’t touch a robot (Imagery, field construction, community service), it’s important that every student have an appropriate avenue for contributing to a robot build, and doing three builds seems like a good way to meet our goals. Ambitious, maybe crazy, but doable.

Robot C will be led by several new mentors and a team of 9th grade students who have shown leadership ability in our off-season training. The goal is to make a viable WCD drive base for testing defensive play against our competition machines. We have a well-established method for designing WCD bases, and will be adding to that the use of REV Ion materials, including the Max Tube extrusion and the Two-Motor Drivetrain Gearbox. Depending on the game and how things go in build season, we may also use this as a test bed for game piece manipulation.

  • We want to share Robot C with folks who want to make an easy, strong and reliable drive base that is a step beyond the AM14U, so we will try to highlight it in ways that benefit those teams through our OA content. We are also excited to try using Python in programming a full robot for the first time, and we know this will be useful for teams who are considering doing the same.

Robot B will be a full test of the REV Ion product line. We want to make a competition-ready machine following the KISS principle. Game dependent, it may attempt to play the whole game or specific parts while “keeping it simple”. Again, depending on the game, we hope to utilize the new REV swerve modules in the drive base design. If we get into the Green Country Regional week 6, this will probably be the robot we compete with there.

  • We want to share Robot B to show our experience with the Ion product line. Many teams are interested in seeing what can be done with Ion and so are we! Hopefully our public struggles, successes and failures with it will help other teams make good purchasing decisions for the future.

Robot A will go with whatever works. For this machine, we still want to follow the KISS principle but without restrictions on materials or suppliers. We (like nearly all of you) have some Vex products in stock and we plan to use the hell out of ‘em rather than throw them in the trash. This robot will likely be the one we compete with at the Colorado and St. Louis Regionals.

  • We want to share Robot A because we do believe in the KISS principle; robots don’t need to be super complicated in order to be successful on the field of play, and we think we can make a competitive robot that isn’t fancy (it worked out well for 2022!). We want to encourage teams to follow this philosophy if they are interested in becoming more competitive, and we look forward to sharing our insights and difficulties with y’all.

As a bonus, each of the three robots will be decorated in line with our theme for the year, KISS (the rock band). Looking forward to rocking out.


1339 has been very concerned about two recent events that affected the FRC community: first, the recent abomination that has been the IFI abusive behavior scandal, and second, the re-emergence of known predatory individuals who attempt to worm into vulnerable teams so that they can abuse students. These events have refocused us on student safety, and have led us to develop a badging system which we intend to implement team-wide in January, and which we will be sharing with the community through OA. As fun as FIRST is, it is only a vehicle for the betterment of students; we believe that student security and safety need to be taken very seriously, and through our OA work, we hope to contribute to a larger discussion and effort to make FRC the safest place we can provide for all the students in FIRST.


We have spent more time as a team thinking about and working on bumpers than most. Bumpers have a set of criteria that are among the most critically important in the game (including whether your team is allowed on the field at all), but have very little crossover with other FRC skills, tools or materials. We are continuing to try to make bumpers easy, quick, durable, protective, and robust, and we will share this adventure with you this year.


For recognizing the value in sharing ideas and progress openly. There are so many teams whose resources (especially institutional knowledge) were depleted over the past three years and we really need to help each other if this program is going to survive for future generations of students. We are honored to have the opportunity to invest in the Open Alliance with y’all.


I kind of hope to see the KISS bot in Tulsa; I am sure it would make the regional more of a challenge. Might hurt the odds for my team to even to make it to the finals but it would be great to share the experience.

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Happy Holidays, Folks!

Everyone at 1339 wishes you the best, safest and most restful of seasons. I am personally grateful that we have several weeks of quiet before kickoff. Our team motto is Robotics Is A Fourth Place Activity, and it’s been very good to see students and mentors relaxing and doing pleasant and fun things.

Here are some things we have been working on for the last while. You can expect in-depth updates on these issues from 1339 team members here, once build season begins in earnest.


Our student programming leads have continued to refine the code for their implementation of the SDS MK4i swerve robot the team built in the fall. One thing I’m particularly impressed with is a new joystick configuration that uses the right thumb joystick (on an X-Box controller) not to spin CW or CCW, but to point the cassis “front” in the direction you wish it to face. @JamesCH95 shared this with @Wesley on team 95, who dubbed it “Absolute Heading Control”, a name I like, but we will see if it sticks with the team. I think you can find our code here: https://github.com/Angelbots1339/2022OffseasonSwerve/blob/main/src/main/java/frc/robot/subsystems/Swerve.java


Our programmers also were able to get this Multiplexer to work with up to eight REV sensors (specifically the color v3 and 2M distance), giving us a much expanded ability to add sensors this year. Here’s a photo:


Our excellent mentors Arturo and Eddie have been working diligently to create a system that securely badges in and out students and mentors, which is part of our effort to increase overall security for ALL FIRST teams, not just our own. Honestly this is getting (and will continue to get) as much or more attention than robot-making. We appreciate the limits within which HQ must work to keep students safe from predatory behavior, but we absolutely think things can be drastically improved. The code for the badging and scanning app (from an authorized phone) will be shared here and elsewhere publicly, in hopes that other teams can implement it and improve upon it. Here’s an early version of the mock-ups:


Mentor Garrett took it upon himself to improve our Shapeoko Pro XL CNC router by creating a tube fixture using these low-profile vises. Total cost was $360 (for three vises) plus several hours of manual machining time. We look forward to greatly improving our ability to accurately cut tube material this year, thanks to this effort.

Machinist student Heather has been working on solving the annoying problem of our tool box top, which adjusts up and allows additional tool storage. Unfortunately the provided tool knocks against our road case, making the process slow and annoying. Heather’s solution is to machine an extension for the handle on our manual mill. Not finished yet, but nicely done Heather!



We are looking at the possibility of doing extra work once the game is released to design field elements. We want to meet certain criteria, including allowing lower-resource teams to quickly and inexpensively create game-specific field elements that will allow them to practice. This depends on many things that we don’t yet know, so there’s not much more to say for now. Here’s hoping the team version of the field this year is inexpensive, easy to read, accurate, easy to build, and compact enough to store!


Have a lovely few weeks, everyone!

Mr. N


Credit where it’s due, we heard about this idea from @mrnoble and accidentally shared it first. Oops!


Additional credit where due, Team 95 has been one of the top five inspirational teams for Team 1339 and me personally for many years, and I am enormously grateful for the work you all put into making our FRC experience better.


Hey, that’s me!

I also installed a new water cooled spindle on the router to play with, we’ll see if it is any significant improvement over the stock router. Just from spinning it up, it’s significantly quieter than the stock router. I’m going to be investigating ways to upgrade the rigidity of the machine in the future too, the shapeoko machines are severely held back by the belt drive system on the X and Y axis, and need to be improved to compete with similarly priced machines I’ve used like the Omio X8.

We will also be switching to Fusion 360 for our CAM this year, and will be teaching our students proper CAM techniques to help further improve our CNC work


The new shapeoko 5 upgraded from belts to ball screws. Mildly annoying as we bought our 4 a few months before they released it

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Howdy folks,

I hope that y’all had a fantastic kickoff. There’s a lot to absorb and think about. Our team met from 8:30 this morning to 5:00 this evening, and we have some observations and have made a few early (Jell-o, not solid) decisions. As I convey these to you, please keep in mind the following guidelines.

  • We have team-specific goals that guide our decisions. These probably do not align with all the goals your team has made.
  • This is early stuff, we reserve the right to be wrong and change our minds.
  • We are particularly interested in Keeping It Simple while being highly competitive (within our team goals). We absolutely want to make a robot that doesn’t have unnecessary complexity.


  • The 2013, 2017 and 2019 games have something to teach us about cycling with unusually shaped game pieces (speaking specifically of the cone here), especially when they fall on the floor or are in a non-ideal orientation. This game has the longest run length for a cycle; longer distance than any of those three games. The game piece is probably most similar to the 2017 piece in terms of how annoying it will be if it’s dropped on the floor, like, in front of your loading area, for instance.
  • The “cube” really doesn’t need to be treated as such; it needs to be treated as a pick-and-place ball, like a beach ball version of 2019. The 2018 cube-orienting jaws are way overkill and unnecessary.
  • L1, L2 and L3 scoring are not equivalent to the 2019 game’s. L1 is on the floor, where you can literally score points by missing your L2 or L3 target. Height is only advantageous in the sense that you could pack more horizontal reach into a taller package.


  • Maximize possibility of winning matches and gaining the other RP’s.
  • Move quickly across the field.
  • Balance (“ENGAGE”) the CHARGE STATION in both auto and end game to improve both raw score, and the chance for an RP.
  • Collect cones from the floor in any orientation.
  • Place cones on the highest level, as early as possible, then move on to the next level.
  • Automate scoring as much as possible, using retro tape and April Tags to align and “just push the button”.


  • Floor cone collector.
  • Cone placement device.
  • Swerve drive.
  • extensive use of gyros and accelerometers to allow balancing in unpredictable circumstances.
  • small footprint, to allow for more balanced partners.
  • Cube collector is a lower priority for early prototyping; can likely be added to cone placement device later.


We can see a viable path for many teams to make very simple robots that play important roles in this game; there are a few more archetypes than we typically foresee. Cubes will pop all the time. Also, somehow I won $5 today from a bet I made with my team back in September.

Have a fabulous and restful evening.

Mr. N



We have learned a few things, and rethought a few things.


No. I was concerned that it would clog loading and scoring areas just by being against the wall, but as Spectrum clearly demonstrated here (and as we discovered as well), it squishes very flat. Right now it feels more like an oddly shaped ball that might require an extra stage to line it up for scoring, but that can use intakes that are fairly standard.


Yes, but if we end up using this we will extensively modify it. The bearings, internal friction blocks, and CF springs are all not ideal, and the tubing is very heavy considering how much of a moment arm it will need to produce. We tested one of our existing climbers turned on it’s side at 90, 45, and 60 degrees relative to vertical. At 45 it bound up a lot, less so the closer we got to horizontal. Here are two videos we took of the testing.

Thrifty Pink Arm Test 1

Thrifty Pink Arm Test 2


Just putting it out there that swerve drive bases don’t need to be squares.

Have a great night!

Mr. N


Another thread marked as “watching”. Expecting great things from y’all! Will be keeping my eye on 1339.


Hi Everybody,
Another small update from our prototypes and testing today. Inspired by some of the testing team 3847 has been doing, we wanted to see what kind of compression we can put on the game pieces without popping or permanently damaging them. We built a simple test frame from some 2x4s we had, and drilled holes every inch to adjust compression levels. We used compliant wheels in our testing today, we did not test with more rigid wheels. We found that we were able to compress the pieces a lot more than we thought. At every compression level, both the cone and the cube fed through the wheels and were not damaged in any way. The only exception to this was the final test we did with the two rollers almost touching each other, we only tested that level of compression on the cone. Some of the videos at max compression are below because I think they are funny to watch. If you want more specific compression tests let me know and I can post videos of our results. Between the testing that team 3847 has done, and this testing tonight I’m confident that the game pieces are more likely to be popped or damaged by things such as sharp corners or screw heads than by compressing them against a wall or in a claw. Good news after how easy game pieces have been destroyed in the past few games!

Cone maximum compression test:

Cube maximum compression test:


Sometimes I feel the same way as this cube


Is the song from Encanto you identify most with “Surface Pressure”? Because bro same.


What kind of modifications are y’all looking to make? We also came up with this idea and are keen on watching this play out. (If you don’t know all good).

If we decide to use one of the telescoping kits (Thrifty, AM Climb-in-a-Box, WCP Greyt) we would probably make the following modifications:

  • Replace the plastic friction blocks inside the tubes with aluminum billet blocks, machined to house 5/8" or larger bearings on all four surfaces
  • Replace the stock CF springs with beefier ones
  • Machine the tubes to make them as light as possible
  • Increase the supported surface (8" or more between stages)

For our first update working with vision, we spent some time getting Photonvision running on an Orange Pi and testing the performance with Apriltags. When we first got it working, the Orange PI was running 3D pose estimation for Apriltags with fps under 10, and latency above 15 ms on the lowest resolution available. In this example we connected directly to the Pi via Ethernet. We are also using an Arducam.

The next day, it started working at 100 fps with latency sometimes lower than 5ms, also on the lowest resolution available and connected directly. The camera was a little toasty, so we added some more cooling to the camera and the Pi.

On the lowest resolution, which was about 320 x 240, we could detect the tags about 10 feet away reliably. This could possibly be increased a bit with better tuned settings, but with high fps and very low latency, it is a bit overkill to have the resolution that low. On the maximum resolution, 1280 x 800, we were getting ok fps around 10, with latency around 50ms. With the resolution a step up from the lowest, at 640 x 480, we were getting 50+ fps with under 15ms latency. Performance with the Orange Pi is great, and it should be more than enough for doing vision this year.




We are done with our meeting times until Saturday, and it’s been a productive week. Very excited to take a few days off from things and absorb ideas for a while. Also excited to sleep and spend time on other stuff!

Today we CAD’ed and CNC’d several intaking prototypes. Since we are Open Alliance we will be happy to share these files with anyone interested; here is the link to the intake roller you’ll see in the videos below.

Untitled design (2)

Self-Aligning Cone

Prior to this, we tested the “pinch” spacing (less than 1/2") in order to see if we could make the cube and cone behave anything like the robot shown here (Iron Panthers 2018) and the answer was no. The medical wrap we used for this test (wrapped around 1.25" polycarbonate tube rollers, spares from our 2022 robot) literally eats the cone material when squeezed too tightly, and the cube just gets rejected after a quick expansion. As shown above, this is about 2" of space between the rollers (3.25" center to center), which worked much better with both game pieces. We were able to get the cone to align itself in the rollers from a number of orientations. We believe that with the addition of another roller and some height adjustments, we might be able to intake both cubes and cones from the floor, and align cones vertically from most angles of attack. This would be a game-changer for us. We will work on this design, create a new prototype, and test it on a moving chassis on Saturday.


It’s going to be incredibly important that we be able to decide on a design and construct it with time to practice cycles and work on programming. We are looking at several factors that will influence our final decisions.

  • Robot Architecture. We want to have as few degrees of freedom as we can manage. We want to reduce drastically the risk of a ridiculously long swing arm and the ensuing carnage (with misalignment being a major problem). A crane (influenced by the robots of the 2013 BEST Competition) and an internal passive alignment (shown here in our 2016 off-season project) are the leading contenders for making a simple robot that can score quickly from all positions. We will let you know what we go with (maybe both).

  • Game Piece(s) Manipulator. This may actually be less important, because we think whatever we choose to go with it will be modular and replaceable with something better later on. Currently the leading candidates are a full-width horizontal roller intake (shown above) or a vertical rolly claw.

  • Vision. Accurately aligning for both intaking and scoring game pieces will be critical and very difficult this year. Teams that think their success in the 2022 game will transfer easily to 2023 are badly deceived and need to face the fact that both acquisition and scoring are much more difficult this year, even discounting that the game pieces are not familiar and behave differently to the balls we’ve had to play with since our seniors were in 8th grade. Be wary! It does look like using vision is much easier if you are further from your goals, rather than parked right in front of them (where the April Tags are). Also worth noting that retro targets disappear once game pieces are scored on them.

That’s all for now. Be safe, have fun, and take breaks!

Mr. N


You should be getting better performance I thknk. Join the Photonvision discord and we can figure this out and find the limiting factor.

Edit: missed the second half of the post. If you end up having any other issues, do not hesitate to reach out.


Did you try your test with the arm rotated 90 degrees to see if it made a difference? Thought is the weight is pinching the spring, if you rotate the arm does it relieve it enough to not bind? No idea if it would help!

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Yes, we tested it vertical, horizontal, and at different angles between. It would take quite a few modifications before i would feel confident it would work consistently, due to the binding you referenced.

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