I’d like to preface by saying 72 hours to build a robot can make or break a team, and at Penn State, I felt closer with my teammates after this experience. Keep in mind this post my opinion, and I am frequently wrong. Getting your own empirical data is recommended.
So lets hop right in! Simply put, the trap is very hard to score in. If you are a newer team, or have less budget/time, I would not recommend making it a priority.
Grabbing off the ground is seemingly most easily done with dual rollers and 0.2 inches of compression. Designing a roller that can grab off of the ground without extending past the 1 foot limit is difficult. Ours ends up going past the limit once our arm swings around, so modifications would be necessary.
A shooter for the speaker is really easy to build. All you need is 2 NEOs with no reduction, and a 550 to feed it in. With 2 inches of compression you won’t need spin, but you won’t shoot as fast. Adding more compression is both recommended and will require spin so when the disk reforms it does not create wobble.
This brings me to my next topic: MAKE AN AMP SCORING MECHANISM!!! The amp has a slanted piece inside that makes it next to impossible to score consistently by shooting up into it. I would highly recommend a design that places it in from above, similar to what Penn State Ri3D did. I predict that not a lot of teams will be good at the amp, so being able to cycle the amp fast should get you picked and result in more wins. It is like how bots last year that could quickly fill up the bottom row with cubes usually did well. The amp is tricky so make sure you have a good prototype. I think a modified version of the CAD in 12 hours would work well for doing amp and speaker.
If you can swerve, do it. There are a lot of routes for defense in this game, and a swerve bot will be able to avoid them more easily. I’ve heard people compare this game to 2016 in levels of defense. On a similar vein, lowbot is key. Going under the stages will help a lot for avoiding defense and decreasing cycle time. It is very much worth it to design a bot that is low enough to go under quickly.
If you want to join a Robot in 3 Days team once you are graduated from FRC, I highly recommend it. It was some of the most fun 72 hours I’ve had, and felt like an extended version of the adrenaline rush from a competition.