Team 4201 2023 Season Documentation

Team 4201 is thrilled to share our 2023 robot, Gridlock, with the FIRST community! We’ve put a lot of hard work into both our CAD and code this season, and we are excited to release our work to the public.

Our code highlights include:

  • Trajectory following with PathPlanner and 4 different auto paths
  • State Machine to define and transition between different scoring, intaking, and stowed states
  • Limelight Pipelines to identify and adjust our chassis towards game pieces in auto
  • Superstructure, LED, and field simulation (with autos) using Wpilib simulation libraries and Pathplanner
    In addition, we had also developed some features that we didn’t get to fully implement in time for the competition season, such as:
  • AprilTags for more accurate localization on the field
  • Intake distance sensors to know when we have a game piece and to automatically put our robot in the stowed state
  • Smart scoring system that would line us up with the closest available node (using apriltag vision) and could be shifted using left/right buttons
    We plan to work on implementing these features during the off-season, and we’re excited to see how they will improve our robot’s performance.

You can find our repository for this season here:

Our robot’s CAD design features:

  • MK4i L3 swerve drive from Swerve Drive Specialties for agile movement
  • 24 in. by 24 in. drivetrain with a height of 4 ¼ in. for stability and maneuverability
  • 3-stage elevator system with a 5 ft extension in under 1 second for efficient scoring
  • Custom 3D printed pulleys and ropes inside 2”x1’’ extrusions for a streamlined design
  • 180° motion of the virtual 4-bar system with fixed sprockets and chain for versatility
  • 3 roller intake attached to the virtual 4-bar, capable of intaking ground cubes and cones standing or tipped
  • Lightweight design with rubber and 3D printed components for enhanced performance

You can also find our Onshape CAD design here:

Our scouting documentation and data are soon to come!

It’s worth noting that during the off-season, we plan to implement AdvantageKit, courtesy of 6238 Mechanical Advantage. As a result, our code will undergo refactoring soon. However, we’re excited to share the code that led us to the Champs with the community. We welcome any feedback or questions you may have!

Wishing you the best!

-Team 4201


4201 has become one of the teams my students are eager to see at competition.
You’ve entered “I wonder what ____ did this year?” territory.

Keep up the good work!


Here’s a gif of our different simulations combined together (robot mech2d, field2d, and simulated autopath)