It Was Not The Final Archetype.
So it turns out I accidentally told a little fib. Oops.
What Were We Planning?
You can read the full design post HERE, but in case you don’t want to do that, here’s a quick summary.
- Combined intake and shooter
- Dual purpose as amp mechanism
- Elevator for trap scoring
- “Trap arm” on top to score the note
Why pivot?
The more I looked at the design, the more the flaws became apparent. When conceptualizing it, I had made too many “just” statements.
- “The robot just has to consistently shoot up into the amp"
- “We just have to assemble the internally rigged belt elevator before week one competition”
It was a lot of design choices driven by what I know how to design(elevators and intakes, not shooters) and fear of a faulty mechanism. If the trap mechanism didn’t work before week 1, we just wouldn’t attach it to the final robot. This design choice actually contributed to the growing pile of issues with the archetype instead of helping it. Let’s go over those.
Issues
- Shooter was blocked by the elevator if we shot from more than 4 feet away from the subwoofer
- Would have to spin 180 during auto to shoot and intake
- OTB intake is more likely to get damaged than UTB intake
- Would almost guarantee losing the game of chicken over the middle notes during auto
- Elevators are hard
- This isn’t really an elevator game, yet I was trying to stick a pretty complicated(albeit compact) elevator onto the robot. That goes directly against Vector’s design principles
- Full width shooters aren’t ideal
- As demonstrated by multiple team’s prototyping, horizontally compressing the note provides the most consistency. With a full width intake/shooter, this is quite literally impossible.
- Middle shooter wheels aren’t ideal
- Again, with a full width intake/shooter it is impossible to not have wheels in the middle of the shooter.
Scope Creep
This is probably the biggest issue and the main driving factor. I would be fine with an unideal shooter, we could always just be a closer shooting bot. I would be fine with a vulnerable OTB intake, we could always just not run mid field note autos. The nail in the coffin however, was how complicated the design was getting. This was the final state of the cad before the pivot. 
Old elevator CAD found HERE and Intake CAD found HERE
There’s a lot of parts there without even having the trap arm on top of the elevator. The further the bot got along, the more complicated it began. Somehow I had shifted from having a vertical elevator with plenty of room for supports to a diagonal elevator with barely any room for supports. With a week one competition, I had to admit to myself that whether we could or couldn’t have assembled it in time for week 1, it wouldn’t have enough code time or driver practice to be as competitive as I would like.
New archetype
So, let’s address the issues.
Problem. Elevator blocks shooter
Solution. Remove the elevator
Problem. OTB intake is too likely to get damaged
Solution. Switch to UTB intake
Problem. Full width shooter + wheels in the center of the shooter unideal
Solution. New shooter design
Problem. Unwieldy intake pivot, too much weight at the end of the arm
Solution. New pivot is better balanced
Problem. Trap mechanism has too many “just” and “as long as” statements
Solution. New trap function has 0 added on mechanical components. If it works it works, if it doesn’t work it’s a regular climb and amp mechanism
Problem. Scope creep
Solution. Removed the elevator, reduced DOFs
Problem. Sketchy amp scoring
Solution. Not a complete issue, but amp scoring could be more consistent if we’re not relying on shooting into the amp
New CAD Progression
KrayonCAD
I spent way less time on Krayon this go around(about an hour instead of a day) since I already had a feel for what I wanted to fix about the old arche.
We’ll have a 95 inspired UTB intake that centers into a pivoting shooter. Flipping the shooter up, we’ll have a neo550 actuated hood that will function as a redirect for our notes to push down into the trap and amp. We’ll be climbing on 111 2020-esque ratchet strap climbers since that’ll allow us to pull down to the bumpers while remaining extremely compact.
Master Sketch
I deep dove into the master sketch this time to try and prevent any issues from popping
up later on.
Nearly Finished Shooter
Chassis + UTB Intake
While the space constraint is fixed, we’ll probably play around with roller spacing to see what works best. Seven dead axle polycarbonate rollers wrapped in either cat’s tongue grip tape or rubber sleeving, driven by two neo 550s.(I didn’t want to deal with reversal gears)
Full Assembly
I think it kind of looks like a tank, which is pretty dope
Inspirations
111 2024 - shooter
111 2020 - climber
95 2024 - undertaker
5987 2024 - self centering
4481 2024 - amp mechanism
Assuming we don’t pivot later in the season this is likely our final final for real this time archetype. As always, all of the cad files are public. If they’re not linked somewhere convenient, feel free to ask here anytime or ping me in the OA discord and I can link the individual docs. Oh Yeah!
