Entry 09 · September 30, 2026 · Engineering Notebook

Meeting Summary

We rebuilt the frame so the ramp would line up and attached the ramp and the rubber band intake. After a few adjustments, the intake grabbed balls well when we spun it by hand. We made two design changes: a wider intake that no longer needs the side screws, and a Core Hex motor for the intake chain drive. Sarah rewrote the drive code, and our test drive showed that the motors are plugged into the wrong ports and the wheels are mounted incorrectly.

Build: Frame Rebuild

Took the robot apart again because the ramp didn't line up with the mounting holes and our beams weren't long enough
Found longer beams, cut them to length, put everything back together, and attached the ramp
Problem: the beams were cut too short, so we can't put in all four screws on the motors. We need new, longer bars to secure the motors and make the frame stronger.

The black 3D-printed ramp mounted on the front of the robot, with the Expansion Hub and wiring behind it — The ramp mounted on the robot

Build: Intake Prototype

Assembled the rubber band intake. It doesn't have a motor yet, so we spun it by hand to test it with pickleballs.
After a few adjustments, it grabs the balls well:
- Moved the intake lower
- Cut the ramp (it's just a prototype, so we cut it to see how it would work)
- Made the ramp angle steeper
Started attaching the intake to the robot, and it worked great

The rubber band intake roller mounted between two uprights in front of the chassis, above the ramp — The rubber band intake mounted in front of the chassis

Testing the intake by hand with a pickleball

Design Changes

No side screws for the intake: we made the rubber band intake a lot wider, so we no longer need screws to feed balls into it. Instead, we'll use a screw to carry the balls up to the turret shooter.
Intake motor: we switched from a Yellow Jacket motor to a Core Hex motor for the intake chain drive. We couldn't find the right gears for the Yellow Jacket's shaft, but we have the correct gears for the Core Hex motor's hexagonal shaft.
3D printing: we printed this ramp at 100% infill. We'll try 90% next time.

Code & Electronics

Added the Expansion Hub to the Driver Station configuration
Sarah started the drive code over from scratch, and we think the code is now fixed
Our test drive showed two hardware problems: the motors are plugged into the wrong ports, and the wheels are mounted incorrectly. The robot drives backward when it should go forward (and vice versa), and turning is still wrong.
We need to decide whether to fix this in the code or swap the motor ports

Test drive that showed the motor and wheel mix-up

Planning & Logistics

The game balls and AprilTags will arrive on Monday
We need PVC pipe to build mock-ups of the flowers
We need to discuss meeting a third day each week, or holding an all-day session once or twice a month

Homework / Action Items

Josh: redesign the ramp to be ½" shorter and ¼" narrower, with a steeper angle so it still reaches the same height, and a longer flat mounting section for the drill holes. Send it to Sarah to print.
Josh: reverse the screw's direction so it carries the balls up to the shooter properly
Sarah: print the flower parts Torin sent and the new ramp, send the code to Torin, and make a sheet of our competition and event schedule for Columbia Bank
Torin: look through the code, and get new, longer bars to replace the beams that were cut too short so the motors can be secured with all four screws
Everyone: brainstorm ideas as needed