In the game FIRST Rapid React, teams scored points by shooting large balls into a center hoop and swinging across rising monkey bars. See game video.
Team 4817 made two robots for this season. I was both the Design Lead and a Co-Mechanical Lead. I led the design and CAD process for the first of these two robots, and was involved with building both of them.
This robot featured 4 new swerve modules we had sourced. The front section had a tower with intaking wheels at the bottom, belts feeding the balls upwards, and a static horizontal single flywheel. The back section had the climb, with one set of arms that worked as a linear slide and another set of arms that rotated.
As the design lead, I was involved in the planning of the robot, validating other member's gear ratio calculations, and giving advice to finetune all aspects of the design. I also CADed the most complicated part of the robot: the climb.
I designed custom bearing guides and mounts for the linear section of the climber and a crazy 400:1 gearbox for the rotation arm. Building it was relatively straightforward as it was designed with the assembly process in mind. This was also the first file were I started to pay attention to organizing my components effectively in the browser and keeping an efficient timeline at the bottom.
For both robots, I worked with my mechanical sub-team to assemble the parts according to the CAD designs. When the CAD is perfect this is relatively straightforward, however, we are an inexperienced high school robotics team. Instead, we had to come up with many creative solutions on the spot.
The other robot was designed by the CAD captain. Admittedly, his robot looks more polished. However, my team's robot turned out to work better as it had the ability to shoot balls into the goal from more positions on the field. I also benefitted from this opportunity to actually manage a team.
Both robots were sent to regional events. The first robot, the one I CADed with team members, won the Judges Award at the Port Hueneme Regional. The second robot, the one I simply helped in the assembly process of, won the Quality Award at the Arizona Valley Regional. Due to COVID-19 restrictions we were unable to travel ourselves to compete, so we relied on the wider FRC community to volunteer to drive our robot for us at these regionals. Considering that, we overall did amazing!
In the end some parts of the my team's robot did not work well. The whole ball shooting system had wiring issues resulting in the robot not being able to shoot at times. (When there were not any electrical issues, the robot did collect and shoot balls smoothly.) The 3D printed mounting bracket between the lift and the chain broke during the regional event. It was found that mounting an alumninium L bracket accomplished the same thing and was actually stronger. Also during the regional, the driving aluminium gear powering the final stage of the rotating arm's gearbox broke into 2 pieces. Usually when designing mechanisms in FRC, CADers do not need to worry about gears and sprockets breaking, but this application applied enough torque that it became an issue. No quick fix for that problem was available, but I realized that double layering the gears and choosing to use steel gears would have probably solved the issue.
Check out these videos to see our team testing our robot in action.