Day 7: Making a few shots and a lot of misses.

Shooter Testing

We modified the shooter from our 2017 robot to be able to launch power cells. It's mounted to our protocube (just a cube made of 2x4s but we find lots of uses for it).

In 2017 it was one 775pro geared 4:1, it's now 2x 775pros geared 2:1. The hood has 1/8" rubber sheet to ensure the ball is rolling and doesn't slip on the polycarbonate panel. This shooter was based on the FRC#33 2017 shooter when be built it that season.

It shoots with 4 solid Fairlane nitrile rollers (RR-754-35W-RP). It also has been setup with two smaller diameter accelerator motors to attempt to have the effects of hand feeding the ball some what mitigated.

We are running it currently without velocity control, we have a small tachometer and it shows that the wheels are spinning at 5700 RPM at full voltage. This shows that the 775pros motors are having trouble getting the wheels anywhere near their free speed.

Video of some of the initial test can be seen on our photo gallery

This shot was about 25ft.

https://photos.spectrum3847.org/2020-FRC/2020-Build-Season/i-F8H8wNg/A

The compression at the tightest was around 2.5" (4.5" from wheel to hood).

Part of goal is to see how we can make consistent shots with a variety of balls. We will continue to play with this shooter setup tomorrow to see how we can improve consistency.

Our next prototype will be moving up to a 6" wheel to get it closer to the correct RPM range for the free speed of NEOs at 1:1 or slightly over driven.

3D Printing Prototype Parts

All this week we have been printing parts for prototypes.

Today we started making some larger parts. Wheel extension on the left, intake ramps on the left.

We have use countless Protopipe parts as well we printed up a bunch of HYPEblocks for the next iteration of our shooter prototype.

Robots that inspired us today

2017 - 33 (shooter)
2019 - 148 (elevator chain attachment)

WCP - Greyt Elevator V2

Sketch of the Day

Figuring out some of our climber geometry

Spectrum