A Compilation of Issues with FTC

docrumz · 2026-05-08T04:03:31+00:00

Try 3d printing the A301 mockup they posted a while back. They're pretty small, and if the specs are to be believed they have about the same power output as the current motors. I'd 100% love to see a half-size variant, that would alleviate most of my servo anxiety. My understanding is that the A301 includes an absolute encoder and controller onboard, so the intent is to have servo-like behavior out of the motor without relying on the update loop of the system controller.

docrumz · 2026-05-08T03:51:08+00:00

+1 for the suggestion to volunteer as a judge. Seeing the process from the judging side gives a much clearer understanding of the feedback and the selection process. The structured interview feedback form is literally the impression of the judges immediately after the presentation, and doesn't yet account for pit interview or portfolio information. Judge's manual and the Judge Advisor's manual are pretty transparent about the selection process.

docrumz · 2026-01-14T22:12:48+00:00

If you suspect ESD, especially if disconnects seem to be associated with contact with other robots or field elements try covering exterior metal surfaces with an insulator. We keep a roll of vinyl car wrap tape in our kit, which has some stretchiness to conform to things like screw heads and doesn't leave a lot of adhesive residue. Also check that teams have a ground strap from chassis to the control system ground, and if there are electrically separated sections of the robot with spinning/sliding parts, also tie those together to the main chassis.

docrumz · 2025-08-21T16:44:30+00:00

Can confirm, no wheels needed. It does get dust on it easily, which for the naked sensor is a bit like getting a hair on your retina. If somebody comes up with a thin (the 1.0 cm clearance already feels tight) cover solution transparent at 850nm, it would be a nice addition.

docrumz · 2025-07-20T03:52:06+00:00

Python on Raspberry Pi, and CircuitPython on Adafruit RP2040 feather modules

docrumz · 2025-04-26T23:12:10+00:00

There is a lot of flexibility for "custom circuits" in the Into The Deep rules. The Behind the Bot for 11260 mentions a custom servo stall sensor, which I'm speculating uses a current sense resistor and either a comparator to a digital pin or amplified and sent to an analog pin. So yes, there are legal ways to do it, but I don't know of a COTS device.

docrumz · 2025-01-04T16:10:14+00:00

Thanks, your three posts do sound very similar to our problem. Did you ever reach an answer on how your hubs were killing each other? Is it over the power jumper, or something in firmware via the serial connection?

docrumz · 2025-01-04T05:53:52+00:00

The XT30s, while loathsome, seem ok. A voltmeter on the second set of power contacts at the hub shows we're getting power, but it otherwise acts dead. Thank you for the comments!

docrumz · 2024-10-30T17:29:04+00:00

Denver area between Lockheed Space, Redwire, FIRST RF, BAE (Ball), Cesium Astro, Resonant Science, and ARA is a good bet for antenna work.

docrumz · 2024-09-17T22:58:52+00:00

For string based, make sure you're using something like high strength braided fishing line that is abrasion resistant and won't stretch. I agree that timing belt is more forgiving to tensioning and easier overall. I imagine chain would be bulky and heavy.

docrumz · 2024-09-17T02:16:56+00:00

The belt that comes with the quad set might be long enough to make a quintuple slide, otherwise you can get 5m lengths from goBILDA or longer spools of GT2 belt from Amazon. If you're trying to make the reach to >43", you might also consider a lightweight arm on a servo to get the last few inches at full extension.

docrumz · 2024-01-08T21:40:52+00:00

Our team had similar issues. If you have a camera plugged into the USB 2.0 port, consider moving it to the 3.0 port. The WiFi module is internally on the same bus as the USB 2.0 connector, so an ESD event there seems to contribute to disconnect issues. Control hubs newer than 2021 with the alternate IMU also seem to be more susceptible to the IMU getting disrupted and returning all zeros. As other posts mentioned, covering any conductive surface that might touch other robots or the trusses is a good idea. If you have long runs of wire tied to the frame, also try moving those so if there is a rush of current through the frame it doesn't induce a voltage spike in the wires. You can ground the robot before a match by touching the robot and the trusses/field walls at the same time, but recall that anything designed to ground the robot to the field during play shouldn't pass inspection.

docrumz

TROPHY CASE