Abstract
This post covers the design, strategy, and lessons learned from Jimmi, Team 7243’s 2024 FRC robot. Built for the CRESCENDO℠ game, Jimmi featured a swerve drive, flywheel-based scoring system, and a Climber-in-a-Box. Over the season, our team iterated from an amp-focused design to a speaker shooter, balancing trade-offs between flexibility, structural strength, and reliability. While we faced setbacks such as mechanical failures and electrical issues, the season ultimately strengthened our technical knowledge, team leadership, and ability to adapt under pressure. This write-up documents the journey from concept to competition, highlighting both our achievements and the challenges we’ll improve on moving forward.
Links
Here are some links to different parts of the robot:
Game
If you haven't seen the reveal for the 2024 game, you can view it here:
The game has two main objectives: score notes into the speaker/amp, and climb on the chain.
Build Season
We started with an idea of only scoring notes into the amp and climbing at the end of the game using a Climber-in-a-Box with a modified hook for chain.
We chose to use a swerve drive for the robot, as it is the strongest holonomic drivetrain available in FRC. Swerve drive is used by most of the top teams in FRC, and the data supports that it increases chances of alliance selection.
Our design also used the apriltags on the field to align the robot to the speaker and amp.
We also planned to use a pneumatic piston to push the notes into a flywheel that would then launch the notes into the amp we used compliant wheels for the flywheels.
After a lot of hard work, we got the amp-scorer working. You can view the video here. I collected all this footage while tuning the control loops for the flywheels and auto-alignment.
We continued with this design until the Coronado scrimmage, four weeks before our regional. At that point, we realized our model of the amp was outdated and different from what would be on the field. With this change, our robot could not consistently score notes into the amp. This was quite devastating, but we persevered and updated our design to feature an adjustable launch angle and a thicker set of flywheels. These allowed our robot to score notes into the speaker, though it forced us to skip the prototyping stage for time’s sake. You can watch a video of the new system in action here. As you can see in this video, the new launcher is quite wobbly, with the top part jiggling back and forth.
Outcomes
You can view our match scores here.
At the competition, our robot suffered some irreparable structural damage, primarily due to our decision to use 1/8" and 1/16" 6061 aluminum sheet for structural parts of the robot. Our adjustable shooter was far too flexible, and when our robot received its second big hit, it flopped around and bent the aluminum sheeting that contained the top part of the game piece elevator.
Beyond this oversight, our robot suffered from general reliability issues stemming from a lack of electrical robustness and haphazard construction.
Our Climber-in-a-Box broke on its first use, and we were so preoccupied with getting the amp-scorer functioning that we didn’t bother trying to fix it.
Overall, the 2024 season was a challenging series of ups and downs, but I wouldn't trade it for the world. As a team without mentors with FRC experience, we made a lot of mistakes that seem pretty stupid in hindsight. Starting an FRC team is already difficult, but making a competitive and consistently high-performing FRC team is a near-impossible task. With this in mind, I believe the 2024 season was a strong step in a positive direction. It grew the knowledge base of our team, strengthened leaders, and helped underclassmen grow into their roles.
Additionally, I met all of my goals for our robot. Some of these include:
- Consistently scoring game pieces
- Closed-loop control for flywheels
- PathPlanner for autonomous routines
- Command-based swerve drivebase
Conclusion
I'm extraordinarily grateful to the mentors, teachers, parents, and sponsors that made the 2024 season possible. It took a lot of time, effort, and sacrifice, but I'm proud of what we accomplished together.