In the 2025 FIRST Robotics Competition game REEFSCAPE, we competed with the coral-placing robot CETO, with a Deep Climb mechanism attached. We did not interact with the Algae in-season, we plan to integrate an algae function in the offseason.

Mechanically it was our second year using SDS Mk4i Swerve modules and Kraken motors, with a super simple superstructure. Our elevator mechanical design used primarily Thrifty Bot kit components, with a stiffened first stage via an oversize spline cross-shaft to drive the chains. The intake mechanism rotates out of the way and collapses against the elevator to allow for a Deep Climb to take place at the end of the match.  

This was our first year using AdvantageKit logging in-season. We used Pathplanner for our autonomous routines. We used TalonFX closed-loop controls (tuned with TunerX) for our elevator positioning, while the rest of the superstructure was simple enough to allow open-loop control modes. We prototyped an auto-alignment feature using the Reef apriltags for in-season use, and got it up to about 70% accuracy in the lab, which was not better than our primary driver after he'd had significant practice.

In official play, we advanced to Semifinals at every Regional we attended, and in our first offseason (NCRI), we were the first pick of the Finalists. 

CAD of the core components is available in Onshape, keeping in mind that the energy chain, energy chain routing and coral deflectors were hand-built additions at the front, as well as the additional plastics and powered wheels on the intake.

The 2025 Competition Robot code is in Github. 

Our 2024 robot Calliope competed at Silicon Valley Regional, San Francisco Regional, Central Valley Regional, and East Bay Regional in season. Over the offseason she competed at Sunset Showdown, Chezy Champs, Capital City Classic, and Madtown Throwdown. Her twin brother Nike joined her at Capital City Classic and Madtown Throwdown. 

Calliope and her twin Nike are Team 841's first "swerve" robots. Outside of the drivetrain, Calliope kept it simple with just six additional motors (none of which required servo precision) and a lot of testing, tuning, and driver practice.

Calliope ran a 1/2" plywood shooter for her first 3 in-season competitions, but eventually swapped to black 1/2" HDPE for her final weekend. The under-bumper intake was two rows of squish wheels on 1/2" hex shafts, and the indexer used additional squish wheels. Our custom telescoping climber arms are 1/4" polycarb - check them out in OnShape, they were super robust and very lightweight. 

Calliope's CAD is here in Onshape 

Calliope's code is here in Github:  https://github.com/Team841/Beta-24

Our 2023 robot "Bia" competed in the Charged Up FRC game at the San Francisco and Silicon Valley Regionals, and the Calgames, Capital City Classic, and Madtown Throwdown off-season events. Bia was a semifinalist at San Francisco, Finalist at Calgames, and Winner at Madtown Throwdown! Our full results are available at https://www.thebluealliance.com/team/841

Bia uses a double-jointed arm with a roller intake to quickly pick cubes and cones from the ground or player stations and place them into all of the scoring locations. 

The roller intake design is inspired by the Everybot and 973's robot reveal, but swaps in larger squish wheels for greater tolerance to game piece misalignment. 

The double jointed arm is built on Rev MAXSplines with bushings riding on 3/4"x1/8" aluminum tube deadaxles. The shoulder is powered by two Falcon 500 motors on MaxPlanetaries, and the elbow uses 1 Falcon 500 on another MaxPlanetary. We use a statemachine to travel between different possible arm poses, including intermediate poses defined to prevent collisions. 

Bia's "West Coast Drive" tank drivebase is geared to go a snappy 16 feet per second using 2 NEO motors per side, on 5" grey rubber Colson wheels. Bia uses an additional pneumatic brake to prevent rolloff after the robot is disabled. We use a PS5 controller for human input, via an arcade drive control scheme with additional smoothing called ChezyDrive. 

Bia's code is publicly available at github.com/Team841/FRC23