FRC 8728 Argonauts - 2023 Open Alliance Build Thread

After a busy off-season, the Argonauts are excited to announce that this will be our 2nd year on Open Alliance! After a great first year and winning Rookie All Star at the First in Michigan district championship, the team could not be more energized to start the 2023 build season.

We plan to share our final robot CAD, publish our GitHub at the end of the season, prototyping and testing videos throughout the build season, and all of our build and competition season photos.

Photo Album: PHOTOS (PUBLIC) - Google Drive

We are all looking forward to the rest of build season and the upcoming competition season!

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Early Season Prototyping and Design Choices

First Steps

The team first read the entire game manual and played Jeopardy to test our knowledge on the rules. We were incredibly grateful to attend the Lawrence Technological University kickoff event and had a great time! The next day, we met at our school’s conference center and completed a PPUT (Points per Unit time) analysis. This allows the team to see what we want our robot to accomplish, how many points we can score, assign a difficulty rank, and a priority rank of each task.

Right after we finished our PPUT analysis, we created a mock field in our school’s conference center to see possible field clogs and cycle paths.

Early Prototypes
We have been making strong progress on our prototypes this year. We plan to have a detailed post about all of our prototypes soon, as we should be completing the main prototyping stage soon. Look out for that soon.


We have finalized our drivetrain for the 2023 season. We are going with an 8 wheel WCD with a top speed of 15.36 ft/s. The team chose the two pneumatic tires in the middle to allow us to possibly use the charge station as a cycle route and the colsons on the outside to give us more pushing power as we believe that the middle of the field will become congested quickly.

Future Posts
We plan on posting a detailed analysis of our prototypes, a shop tour, and what our robot concept is looking like later this week. Apologies for the late post, as midterms are eating up many of our students’ time.

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Design decisions and drivetrain manufacturing

Robot Design
The team has collectively chosen what the robot’s primary mechanisms will be, we have decided on a wheel/claw intake with a tilted elevator on a turret. Since we have gone with a tank drivetrain, we know that the turret will help us save time while cycling and allow us to score without lining the drive base to perfection at the gate.

Instead of belting or using chain to drive the turret, we have decided to direct drive the lazy susan with a Neo on a max planetary gearbox. We think the space lost using a direct drive setup will be worth the fewer complexities we would have with a chain or belt driven turret.

During the off-season, the team bought the thrifty bot elevator, which we plan to use this year to reduce the amount of time spent designing and machining a custom elevator.

Drivetrain Manufacturing
We have gotten all the gearbox plates cut out on our CNC and are expecting the gearboxes to be assembled by our next meeting. We plan to finish the drivetrain by next week, so we can hand it off to the controls team.

The Controls team has been working on configuring limelight for the reflective tape as well as the new AprilTags added in this year’s game. The robot during the game will be programmed to locate reflective tape and AprilTags to align the robot and score more points. The Controls team has also worked on adding preliminary PID code as well as coding the Drivetrain. The PID code will be used for turning and driving in autonomous mode, as well as smoothing out the Drivetrain when driving in teleoperated mode.


Manufacturing and Final Design

This week, we completed our field build that includes a half charge station and one grid.

The build team made good progress on the drivetrain, with the chassis cut out and halfway through with assembly. We should be able to get it done by the middle of this week. We had a lot of issues with tolerance on our OMIO CNC, so it took some time for us to find out what to adjust in our CAD and CAM.

We are getting our turret plates cut out on Monday with a water jet we have access to, so we plan to run build for the turret parallel with the drivetrain.

CAD for the elevator is mostly done, and we should be able to assemble the elevator this week.

Our intake/manipulator team is currently in the CAD process and should be close to a final design.

Subsystem Code
Once the team decided on the designs for the subsystems, the controls team got right to work on an outline for the code for the subsystems. The team worked on coding the base code for the manipulator (subsystem responsible for manipulation of game pieces) which will require 1 motor and pneumatics. The team also worked on the code for the elevator and the rest of the pneumatics required to control both the manipulator and elevator.

The team also added PID loops for the elevator, which will be based on the position read from the encoder in the elevator’s motor. It will then set an output which will get the robot’s elevator to the desired position.

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How are you constructing the pivot for the elevator? It’s hard to tell from the pictures, but from a first impression it looks a bit weak for the length of the elevator its supporting. And the pistons as well look a bit small, but that could just be from the scale of the image. Have you done any calculations/simulations on that part of the system?

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So the mount has a Thunder Hex shaft on both sides, and we saw similar designs from PINK elevators also it has 4 bearings on each side to keep it stable. The pivot is powered by a 3/4 in. bore with a stroke of 4 inches. Here is a better angle.

Week 4 Blog

The team got both gearboxes and were able to chain the drivetrain up earlier this week, allowing us to get our test bench and see how the gearboxes run. While running smooth, we want to get our covers completed before we run the robot on carpet. Next step is to get electronics mounted and wired up!

While we were happy to get the turret structure mounted this week, we planned to get the turret running today, but we ran into clearance issues with our turret plates. The turret mounting plates will be fixed next week and the controls team should have a working turret they can start testing with on Tuesday.

This week has been filled with machining the 2x1 rails for our thrifty bot elevator, all the structure for it will be done on Tuesday, allowing for a quick assembly to take place. We bought bare 2x1 stock this year from a local supplier, but the MAXTube from REV is something we may switch over to next year.

Our team made some design changes, so our programming team made changes to the code. We added code for the intake and the required pneumatics for the robot. We also worked on adding code for the color sensor. We plan on using the color sensor to identify what object we are about to pick and activate the required mechanisms to pick it up. We also worked on configuring the limelight. We are able to pull data that measures the distance between the limelight crosshair and the AprilTags. We will use this data to find out the distance between use and certain game objects. Break Mode feature was also added to stop the robot if needed.


Hey all,

Week 5 was fairly productive for the team and made an immense amount of progress on our subsystems. We got to a lot of testing and were finally able to hand the drivetrain and turret to the controls team!

Week Five Highlights

Design - Not much was done on the design side of the team, as we were able to start the manufacturing of our intake and gripper. The team is starting to look at improvements that can be made before and after the Kettering 1 District Event.

Controls - Controls this week finalized the bade code for the robot, and has started focusing their attention toward autonomous and sensor development. We are also starting to test robot functionality as assembly completes.

Manufacturing - We have finished most of the major CNC work for the year, but continue to cut out small or revisions of parts.

Assembly - As the assembly team finished putting the drivetrain and turret together, most of the focus was placed on the elevator. All we need to do on the elevator is finish the rigging and mount to the turret!


Here’s the mount from the elevator to the turret, which includes our pivot point.

turret be movin
Turret testing earlier this week

The robot in its current state, the top turret plate was taken off to start the mounting process.

dt be movin
Testing the drivetrain on Saturday

We are hoping that we can have a mostly finished robot by Tuesday, best of luck to teams in the next couple of weeks!

I’d love to hear a little about how you’re supporting the turret under such large loads from the extended elevator

Of course, so both the bottom and top turret plates are quarter inch aluminum which are attached to the 1x1 structure that we have mounted to the drive rails themselves. We plan on adding more 1x1 support that runs against the width of the turret, this will be under the bottom plate. If we notice any signs of stress in the structure, we plan to cut standoffs and mount those to the bottom of the 1x1 frame to the top of the drive rails.

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What’s up all,

Week 6 was pretty stressful but exciting as our robot finally came together. We were able to get the elevator and turret mounted to the rest of the robot and are expecting to start testing tomorrow. Here are some quick highlights!

We had some space at the front of our robot, so we decided to use that to mount a second intake, that can help and feed other robots or make feeding to our robot easier. The intake is currently a simple claw, since we have two ways to manipulate the game pieces.


Our second manipulator is a modified version of the 118 every bot intake, as it fits our robot’s needs perfectly. The second intake is also able to pick from the floor and human player station, as it is on an arm and a wrist.

Arm and manipulator mounted to elevator


We finished the rigging of our elevator early last week, which went fairly smooth. Excited to test under power this week!

Here is a close up of our hinged elevator, the current hard stops have to be modified but should be ready by tomorrow.

Hyped to share some more pictures and videos in the next couple of days!

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